diff --git a/htdocs/product/class/product.class.php b/htdocs/product/class/product.class.php
index 8b7d27073c0..9e100871537 100644
--- a/htdocs/product/class/product.class.php
+++ b/htdocs/product/class/product.class.php
@@ -1877,6 +1877,9 @@ class Product extends CommonObject
         if (empty($newnpr)) {
             $newnpr = 0;
         }
+        if (empty($newminprice)) {
+        	$newminprice = 0;
+        }
 
         // Check parameters
         if ($newvat == '') {