This research employed an experimental design to study the issue of gambling to determine the main and interaction effects of Rotter's personal locus of control and situational locus of control on the amount of betting in a simulated blackjack card game. A total number of 53 undergraduates from a private university in Kuala Lumpur participated in this research. A two-way factorial ANOVA was employed and showed no significant main effects of personal and situational locus of control on the amount of betting. The findings also suggested no significant interaction effect between both measures. With current statistics showing an increase in the number of gamblers, especially among youths in Malaysia, the findings of this research could provide insights into the possible factors contributing to gambling behaviour despite the non-significant effects of personal and situational locus of control. © Universiti Putra Malaysia Press.