PURPOSE: To provide better service for a customer who makes a little purchase.

CONSTITUTION: A merchandise data processing device 10 is provided with a CPU 11, a ROM 12 storing the control microprogram controlling various operations including the service point addition processing by the sales product, a RAM 13 storing the data to be used for operation and the result of arithmetic operation, and a note printing section 17 printing notes based on the point. The RAM 13 is provided with an area 33 operating the CPU 11 including a PLU file 31 storing the service point data of the name of the merchandise, unit price, and sales product using a merchandise code and a point work area 32 storing the accumulated service point. Thus, the service point can be presented with a customer who purchases the sales product regardless of the purchase price.