Effects of winning versus losing on the resulting gambling behavior and the relationships with affects were experimentally investigated in healthy undergraduates. Participants (N=20) performed the Game of Dice Task that consisted of 18 gambling trials. Participants played the game twice (Sessions 1 and 2), and their positive and negative affects were measured before Session 1, between Sessions 1 and 2, and after Session 2. Result indicated that participants shifted their gambling choice to be more reckless, after they had experienced wins than losses. In addition, positive affect between Sessions 1 and 2 was positively correlated with reckless gambling in both Session 1 and 2. It is suggested that the effects of winning versus losing and affect are both important for understanding the basic mechanisms of gambling behavior.