The invention provides an automatic transaction system and an automatic account checking method thereof. The automatic transaction system is provided with an upper layer system and a self-service device. The self-service device is provided with a cycling cash box, an identification part, a recycling cash box, a sending part, a receiving part, a storage part and a control part. Before the control part automatically checks the account, the control part writes the recycling cash box balance at this moment to the storage part as the recycling cash box balance before the account checking and when the automatic account checking is finished normally and the recycling cash box balance is definite, after the automatic account checking, the recycling cash box balance before the account checking is read out from the storage part. The recycling cash box balance after the account checking is calculated by adding the recycling amount recycled in the recycling cash box in the automatic account checking, the recycling cash box balance after the account checking is used to update the recycling cash box balance stored in the storage part, the updated recycling cash box balanced is reported to the upper system and the transaction starts over. Thus, the recycling operation burden of workers on the self-service device can be reduced, usage rate of the self-service device is increased and operation efficiency of the self-service device is increased.