PURPOSE : A product lottery service operating system which volatility of a real price is reflected is provided to automatically determine whether or not a lottery is sold corresponding to a real price of a sales product which a market situation is reflected in real time, thereby increasing flexibility for volatility of the market situation.CONSTITUTION : A sales product management server(100) stores basic information of a sales product in a database. The sales product management server provides the basic information to connected clients. A lottery issuing server(200) sells lotteries to buyers by issuing the same. A variability reflecting server(300) determines whether or not sales of the lotteries are ended by comparing a real price of the sales product with the amount of accumulated money of sold lotteries.[Reference numerals] (100) Sales product management server; (110) Area management unit; (120) Product type management unit; (130) Price management unit; (140) Sales product management unit; (200) Lottery issuing server; (210) Lottery generating unit; (220) Lottery issuing unit; (230) Offline issuing unit; (300) Variability reflecting server; (310) Lottery sale price calculating unit; (320) Product price determining unit; (330) Issuing interruption determining unit; (600) Client terminalCOPYRIGHT KIPO 2013