To prevent the efficiency of accounting processing from lowering even when a large amount of merchandise is purchased by one customer.

A merchandise registration processor 1 where a packing table 2 constituted of a shopping basket table 7 and a registered merchandise placing table 8 are arranged at the right and the left parts of an input device 3 is configured by mounting an extension base 9 formed so as to be freely bent and rotatable with the central part as an axis 12 on the registered merchandise placing table 8, and by extending an area where the merchandise on the registered merchandise placing table 8 can be placed by opening the extension base 9 in a flat state.