The invention discloses a clearance compensation structure used during folding and flatwise laying of second-row seats and third-row seats. The clearance compensation structure is used for compensating clearances formed between the second-row seats and the third-row seats when backrests of the second-row seats and the third-row seats are folded and flatwise laid forwards; the clearance compensation structure comprises compensation plates, first containing cavities which are formed in the lower ends of backing plates of the backrests of the second-row seats and used for containing the front ends of the compensation plates and second containing cavities which are formed in the portions, corresponding to the first containing cavities, of the upper ends of backing plates of the backrests of the third-row seats and used for containing the back ends of the compensation plates; when the backrests of the second-row seats and the third-row seats are folded and flatwise laid forwards, the front ends of the compensation plates are contained in the first containing cavities, the back ends of the compensation plates are contained in the second containing cavities, and therefore the middle sections of the compensation plates can compensate the clearances formed between the second-row seats and the third-row seats. According to the clearance compensation structure, the clearances formed when the backing plates of the backrests of the second-row seats and the third-row seats are folded and flatwise laid forwards can be compensated.