A mechanism for treat choosing game sets includes a choosing device including at least one treat received in a box and the at least one treat is connected to a plate made by magnetic material. A rotation disk connected with the plate via a magnetic member located therebetween. A rotation device includes a motor and a transmission device which is driven by the motor. The transmission device includes a shaft and a belt wheel driven by the motor, a belt connected between the belt wheel and the shaft. The magnetic member is connected to the shaft and magnetically connected to the plate. When the box in which the at least one treat is received is stopped by the player, the transmission device drives the rotation disk as usual while the magnetic member is rotated relative to the plate.