To facilitate update management of commodity information while suppressing increase in capacity of a database in a commodity retrieval system using pattern matching by image patterns.

A user terminal 1 transmits an image pattern of a desired commodity to an image processing server 2 through a communication network. The server 2 compares this image pattern with preliminarily stored standard patterns of commodities to retrieve similar/matched commodities. Commodity recognition information for specifying the retrieved commodities is transmitted to shop servers 3 which are dispersively arranged in each area through the communication network. The servers 3 accept the commodity recognition information and return information of the commodities to the server 2. The server 2 integrates the commodity information transmitted from each server 3 and transmits it to the user terminal 1. Since only standard patterns of commodities are stored in the the database of the server 2, the increase in capacity can be prevented. Further, since the momentarily changing commodity information is stored in databases on the distributed shop server side, update management of the database is also facilitated.