diff --git a/htdocs/bom/bom_card.php b/htdocs/bom/bom_card.php
index 7d83a88ce55..baf6e3e1a91 100644
--- a/htdocs/bom/bom_card.php
+++ b/htdocs/bom/bom_card.php
@@ -148,8 +148,17 @@ if (empty($reshook)) {
 		$error = 0;
 
 		// Set if we used free entry or predefined product
-		$idprod = (int) GETPOST('idprod', 'int');
-		$bom_child = (int) GETPOST('bom_select', 'int');
+		$bom_child_id = (int) GETPOST('bom_id', 'int');
+		if ($bom_child_id > 0) {
+			$bom_child = new BOM($db);
+			$res = $bom_child->fetch($bom_child_id);
+			if ($res) {
+				$idprod = $bom_child->fk_product;
+			}
+		} else {
+			$idprod = (int) GETPOST('idprod', 'int');
+		}
+
 		$qty = price2num(GETPOST('qty', 'alpha'), 'MS');
 		$qty_frozen = price2num(GETPOST('qty_frozen', 'alpha'), 'MS');
 		$disable_stock_change = GETPOST('disable_stock_change', 'int');
@@ -173,7 +182,7 @@ if (empty($reshook)) {
 			$bomline = new BOMLine($db);
 			$bomline->fk_bom = $id;
 			$bomline->fk_product = $idprod;
-			$bomline->fk_bom_child = $bom_child;
+			$bomline->fk_bom_child = $bom_child_id;
 			$bomline->qty = $qty;
 			$bomline->qty_frozen = (int) $qty_frozen;
 			$bomline->disable_stock_change = (int) $disable_stock_change;
diff --git a/htdocs/bom/class/bom.class.php b/htdocs/bom/class/bom.class.php
index 0520c76dde2..4923e9d0ca2 100644
--- a/htdocs/bom/class/bom.class.php
+++ b/htdocs/bom/class/bom.class.php
@@ -1064,26 +1064,41 @@ class BOM extends CommonObject
 				$tmpproduct->cost_price = 0;
 				$tmpproduct->pmp = 0;
 
-				$result = $tmpproduct->fetch($line->fk_product, '', '', '', 0, 1, 1);	// We discard selling price and language loading
-				if ($result < 0) {
-					$this->error = $tmpproduct->error;
-					return -1;
-				}
-				$line->unit_cost = price2num((!empty($tmpproduct->cost_price)) ? $tmpproduct->cost_price : $tmpproduct->pmp);
-				if (empty($line->unit_cost)) {
-					if ($productFournisseur->find_min_price_product_fournisseur($line->fk_product) > 0) {
-						$line->unit_cost = $productFournisseur->fourn_unitprice;
+				if (empty($line->fk_bom_child)) {
+					$result = $tmpproduct->fetch($line->fk_product, '', '', '', 0, 1, 1);	// We discard selling price and language loading
+					if ($result < 0) {
+						$this->error = $tmpproduct->error;
+						return -1;
+					}
+					$line->unit_cost = price2num((!empty($tmpproduct->cost_price)) ? $tmpproduct->cost_price : $tmpproduct->pmp);
+					if (empty($line->unit_cost)) {
+						if ($productFournisseur->find_min_price_product_fournisseur($line->fk_product) > 0) {
+							$line->unit_cost = $productFournisseur->fourn_unitprice;
+						}
+					}
+
+					$line->total_cost = price2num($line->qty * $line->unit_cost, 'MT');
+
+					$this->total_cost += $line->total_cost;
+				} else {
+					$bom_child= new BOM($this->db);
+					$res = $bom_child->fetch($line->fk_bom_child);
+					if ($res>0) {
+						$bom_child->calculateCosts();
+						$this->total_cost += $bom_child->total_cost;
+					} else {
+						$this->error = $bom_child->error;
+						return -2;
 					}
 				}
 
-				$line->total_cost = price2num($line->qty * $line->unit_cost, 'MT');
-
-				$this->total_cost += $line->total_cost;
 			}
 
 			$this->total_cost = price2num($this->total_cost, 'MT');
-			if ($this->qty) {
+			if ($this->qty > 0) {
 				$this->unit_cost = price2num($this->total_cost / $this->qty, 'MU');
+			} elseif ($this->qty < 0) {
+				$this->unit_cost = price2num($this->total_cost * $this->qty, 'MU');
 			}
 		}
 	}
diff --git a/htdocs/bom/tpl/objectline_create.tpl.php b/htdocs/bom/tpl/objectline_create.tpl.php
index 7419c4618e0..0a3a3b34e7a 100644
--- a/htdocs/bom/tpl/objectline_create.tpl.php
+++ b/htdocs/bom/tpl/objectline_create.tpl.php
@@ -109,7 +109,7 @@ if (!empty($conf->product->enabled) || !empty($conf->service->enabled)) {
 if (!empty($conf->global->BOM_SUB_BOM)) {
 	print '<br><span class="opacitymedium">'.$langs->trans("or").'</span><br>'.$langs->trans("BOM");
 	// TODO Add component to select a BOM
-	print '<select id="bom_select" name="bom_select"><option value="-1">TODO</option></select>';
+	$form->select_bom();
 }
 print '</td>';
 
diff --git a/htdocs/bom/tpl/objectline_view.tpl.php b/htdocs/bom/tpl/objectline_view.tpl.php
index 82626c12fec..4360d521036 100644
--- a/htdocs/bom/tpl/objectline_view.tpl.php
+++ b/htdocs/bom/tpl/objectline_view.tpl.php
@@ -41,7 +41,7 @@ if (empty($object) || !is_object($object)) {
 }
 
 
-global $forceall, $senderissupplier, $inputalsopricewithtax, $outputalsopricetotalwithtax;
+global $forceall, $senderissupplier, $inputalsopricewithtax, $outputalsopricetotalwithtax, $langs;
 
 if (empty($dateSelector)) {
 	$dateSelector = 0;
@@ -83,8 +83,10 @@ $tmpproduct->fetch($line->fk_product);
 $tmpbom = new BOM($object->db);
 $res = $tmpbom->fetch($line->fk_bom_child);
 if ($tmpbom->id > 0) {
-	print $tmpbom->getNomUrl(1);
 	print '<a class="collapse_bom" id="collapse-'.$line->id.'" href="#">' . (empty($conf->global->BOM_SHOW_ALL_BOM_BY_DEFAULT) ? '(+)' : '(-)') . '&nbsp;</a>';
+	print $tmpproduct->getNomUrl(1);
+	print ' '.$langs->trans('or').' ';
+	print $tmpbom->getNomUrl(1);
 } else {
 	print $tmpproduct->getNomUrl(1);
 	print ' - '.$tmpproduct->label;
@@ -176,7 +178,7 @@ if ($action == 'selectlines') {
 print '</tr>';
 
 // Select of all the sub-BOM lines
-$sql = 'SELECT rowid, fk_bom_child, fk_product FROM '.MAIN_DB_PREFIX.'bom_bomline AS bl';
+$sql = 'SELECT rowid, fk_bom_child, fk_product, qty FROM '.MAIN_DB_PREFIX.'bom_bomline AS bl';
 $sql.= ' WHERE fk_bom ='. (int) $tmpbom->id;
 $resql = $object->db->query($sql);
 
@@ -199,21 +201,23 @@ if ($resql) {
 			print '<tr class="sub_bom_lines" parentid="'.$line->id.'">';
 		}
 
-		// Product
-		print '<td style="padding-left: 5%" id="sub_bom_product_'.$sub_bom_line->id.'">'.$sub_bom_product->getNomUrl(1).'</td>';
-
-		// Sub-BOM
-		if ($sub_bom_line->fk_bom_child > 0) {
-			print '<td id="sub_bom_bom_'.$sub_bom_line->id.'">'.$sub_bom->getNomUrl(1).'</td>';
+		// Product OR BOM
+		print '<td style="padding-left: 5%" id="sub_bom_product_'.$sub_bom_line->id.'">';
+		if (!empty($obj->fk_bom_child)) {
+			print $sub_bom_product->getNomUrl(1);
+			print ' '.$langs->trans('or').' ';
+			print $sub_bom->getNomUrl(1);
 		} else {
-			print '<td id="sub_bom_bom_'.$sub_bom_line->id.'">&nbsp;</td>';
+			print $sub_bom_product->getNomUrl(1);
+			print '</td>';
 		}
 
 		// Qty
-		print '<td class="linecolqty nowrap right" id="sub_bom_qty_'.$sub_bom_line->id.'">'.price($sub_bom_line->qty * $line->qty, 0, '', 0, 0).'</td>';
 		if ($sub_bom_line->qty_frozen > 0) {
-			print '<td class="linecolqtyfrozen nowrap right" id="sub_bom_qty_frozen_'.$sub_bom_line->id.'">'.$sub_bom_line->qty_frozen.'</td>';
+			print '<td class="linecolqty nowrap right" id="sub_bom_qty_'.$sub_bom_line->id.'">'.price($sub_bom_line->qty, 0, '', 0, 0).'</td>';
+			print '<td class="linecolqtyfrozen nowrap right" id="sub_bom_qty_frozen_'.$sub_bom_line->id.'">'.$langs->trans('Yes').'</td>';
 		} else {
+			print '<td class="linecolqty nowrap right" id="sub_bom_qty_'.$sub_bom_line->id.'">'.price($sub_bom_line->qty * $line->qty, 0, '', 0, 0).'</td>';
 			print '<td class="linecolqtyfrozen nowrap right" id="sub_bom_qty_frozen_'.$sub_bom_line->id.'">&nbsp;</td>';
 		}
 
@@ -230,18 +234,20 @@ if ($resql) {
 		// Cost price if it's defined
 		if ($sub_bom_product->cost_price > 0) {
 			print '<td class="linecolcost nowrap right" id="sub_bom_cost_'.$sub_bom_line->id.'">'.price($sub_bom_product->cost_price * $line->qty).'</td>';
-			$total_cost.= $sub_bom_product->cost_price * $line->qty;
+			$total_cost+= $sub_bom_product->cost_price * $line->qty;
 		} elseif ($sub_bom_product->pmp > 0) {	// PMP if cost price isn't defined
 			print '<td class="linecolcost nowrap right" id="sub_bom_cost_'.$sub_bom_line->id.'">'.price($sub_bom_product->pmp * $line->qty).'</td>';
 			$total_cost.= $sub_bom_product->pmp * $line->qty;
 		} else {	// Minimum purchase price if cost price and PMP aren't defined
-			$sql_supplier_price = 'SELECT MIN(price) AS min_price FROM '.MAIN_DB_PREFIX.'product_fournisseur_price';
+			$sql_supplier_price = 'SELECT MIN(price) AS min_price, quantity AS qty FROM '.MAIN_DB_PREFIX.'product_fournisseur_price';
 			$sql_supplier_price.= ' WHERE fk_product = '. (int) $sub_bom_product->id;
 			$resql_supplier_price = $object->db->query($sql_supplier_price);
 			if ($resql_supplier_price) {
 				$obj = $object->db->fetch_object($resql_supplier_price);
-				print '<td class="linecolcost nowrap right" id="sub_bom_cost_'.$sub_bom_line->id.'">'.price($obj->min_price * $line->qty).'</td>';
-				$total_cost+= $obj->min_price * $line->qty;
+				$line_cost = $obj->min_price/$obj->qty * $sub_bom_line->qty;
+
+				print '<td class="linecolcost nowrap right" id="sub_bom_cost_'.$sub_bom_line->id.'">'.price($line_cost).'</td>';
+				$total_cost+= $line_cost;
 			}
 		}
 
diff --git a/htdocs/core/class/html.form.class.php b/htdocs/core/class/html.form.class.php
index ff5f5d0d0a5..b885c4c1acd 100644
--- a/htdocs/core/class/html.form.class.php
+++ b/htdocs/core/class/html.form.class.php
@@ -2367,6 +2367,69 @@ class Form
 		}
 	}
 
+	// phpcs:disable PEAR.NamingConventions.ValidFunctionName.ScopeNotCamelCaps
+
+	/**
+	 *  Return list of BOM for customer in Ajax if Ajax activated or go to select_produits_list
+	 *
+	 * @param int $selected Preselected BOM id
+	 * @param string $htmlname Name of HTML select field (must be unique in page).
+	 * @param int $limit Limit on number of returned lines
+	 * @param int $status Sell status -1=Return all bom, 0=Draft BOM, 1=Validated BOM
+	 * @param int $type type of the BOM (-1=Return all BOM, 0=Return disassemble BOM, 1=Return manufacturing BOM)
+	 * @param string $showempty '' to not show empty line. Translation key to show an empty line. '1' show empty line with no text.
+	 * @param string $morecss Add more css on select
+	 * @param string $nooutput No print, return the output into a string
+	 * @param int $forcecombo Force to use combo box
+	 * @return        void|string
+	 */
+	public function select_bom($selected = '', $htmlname = 'bom_id', $limit = 0, $status = 1, $type = 1, $showempty = '1', $morecss = '', $nooutput = '', $forcecombo = 0)
+	{
+		// phpcs:enable
+		global $conf, $user, $langs, $db;
+
+		require_once DOL_DOCUMENT_ROOT.'/product/class/product.class.php';
+
+		$error = 0;
+		$out = '';
+
+		if (!$forcecombo) {
+			include_once DOL_DOCUMENT_ROOT.'/core/lib/ajax.lib.php';
+			$out .= ajax_combobox($htmlname, $events, getDolGlobalInt("PRODUIT_USE_SEARCH_TO_SELECT"));
+		}
+
+		$out .= '<select class="flat'.($morecss ? ' '.$morecss : '').'" name="'.$htmlname.'" id="'.$htmlname.'">';
+
+		$sql = 'SELECT b.rowid, b.ref, b.label, b.fk_product';
+		$sql.= ' FROM '.MAIN_DB_PREFIX.'bom_bom as b';
+		$sql.= ' WHERE b.entity IN ('.getEntity('bom').')';
+		if (!empty($status)) $sql.= ' AND status = '. (int) $status;
+		if (!empty($type)) $sql.= ' AND status = '. (int) $type;
+		if (!empty($limit)) $sql.= 'LIMIT '. (int) $limit;
+		$resql = $db->query($sql);
+		if ($resql) {
+			if ($showempty)	{
+				$out .= '<option value="-1"';
+				if (empty($selected)) $out .= ' selected';
+				$out .= '>&nbsp;</option>';
+			}
+			while ($obj = $db->fetch_object($resql)) {
+				$product = new Product($db);
+				$res = $product->fetch($obj->fk_product);
+				if ($obj->rowid == $selected) $out .= '<option value="'.$obj->rowid.'" selected>'.$obj->ref.' - '. $product->label .' - '.$obj->label.'</option>';
+				$out .= '<option value="'.$obj->rowid.'">'.$obj->ref.' - '.$product->label .' - '. $obj->label.'</option>';
+			}
+		} else {
+			$error++;
+			dol_print_error($db);
+		}
+		if (empty($nooutput)) {
+			print $out;
+		} else {
+			return $out;
+		}
+	}
+
 	// phpcs:disable PEAR.NamingConventions.ValidFunctionName.ScopeNotCamelCaps
 	/**
 	 *	Return list of products for a customer.