PURPOSE: To prevent same products from being collectively detected at every delivery for detecting the products in a delivery product detection device using a bar code added to the products.

CONSTITUTION: An area storing product-detected quantity and product-detecting quantity in accordance with product detection information at every delivery unit, which has a product code and the quantity of the products to be delivered, is provided for a storage part 5. When a bar code reader 1 reads the product code of the detected product, a product detection information operation comparison part 4 sets product-detecting quantity corresponding to the detected product to be '1', sets previous product-detecting quantity to be zero even if there is the reading of any product code, and decides the number of the detected products in addition to product-detected quantity. Then, product-detecting quantity, which is read this time, is set to be '1'. When a numeric is inputted from a keyboard by following the reading of the product code, product-detecting quantity is changed to the numeric value as collective product detection input. When product-detected quantity is updated, it is checked whether the number off updating times reaches quantity to be delivered or not.