diff --git a/htdocs/product/class/product.class.php b/htdocs/product/class/product.class.php
index 7135f2b20ab..bb245d8307c 100644
--- a/htdocs/product/class/product.class.php
+++ b/htdocs/product/class/product.class.php
@@ -886,7 +886,7 @@ class Product extends CommonObject
 			$sql.= ", surface_units = " . ($this->surface_units!='' ? "'".$this->db->escape($this->surface_units)."'" : 'null');
 			$sql.= ", volume = " . ($this->volume!='' ? "'".$this->db->escape($this->volume)."'" : 'null');
 			$sql.= ", volume_units = " . ($this->volume_units!='' ? "'".$this->db->escape($this->volume_units)."'" : 'null');
-			$sql.= ", fk_default_warehouse = " . (! empty($this->fk_default_warehouse) ? $this->db->escape($this->fk_default_warehouse) : 'null');
+			$sql.= ", fk_default_warehouse = " . ($this->fk_default_warehouse > 0 ? $this->db->escape($this->fk_default_warehouse) : 'null');
 			$sql.= ", seuil_stock_alerte = " . ((isset($this->seuil_stock_alerte) && $this->seuil_stock_alerte != '') ? "'".$this->db->escape($this->seuil_stock_alerte)."'" : "null");
 			$sql.= ", description = '" . $this->db->escape($this->description) ."'";
 			$sql.= ", url = " . ($this->url?"'".$this->db->escape($this->url)."'":'null');