Abstract: In the present study, the differences between addictive memory and ordinary memory were investigated by morphine-induced and food-induced conditioned place preference (CPP) in adolescent and adult mice. The result showed that: 1) morphine-induced CPP could be established in adult mice but not in adolescent mice. 2) food-induced CPP could be established both in adolescent and adult mice. This study indicated that between adolescent and adult mice, there was no difference in ordinary memory, but for addictive memory, they were quite different. Our data suggested that the development of addictive memory and ordinary memory system in mouse brain might not be paralleled.