Automobile seat capable of being refitted and laid flat on rear side

The invention belongs to the technical field of seats, and particularly relates to an automobile rear-side seat capable of being refitted and laid flatly, the automobile rear-side seat comprises a connecting support lug, a rear seat base, a mounting support lug, a first limiting mechanism, a rear seat backrest and a second limiting mechanism, a protruding area exists on the bottom face of the front side of a rear seat of an existing automobile body, and in order to prevent the protruding area from affecting laying down of the rear-row seat, the rear-row seat can be placed flatly. When the rear seat backrest is folded, the two top elastic side cushions can be folded relative to the bottom elastic cushion, a concave area is formed between the two top elastic side cushions after folding, and after the rear seat is completely prevented from falling, the concave area just corresponds to the convex area on the bottom surface, so that the rear seat backrest is prevented from falling. By means of the design, the impr