A car seat comprises front supports and rear supports, wherein the front supports support a front frame structure of a seat; the rear supports support a rear frame structure of the seat; the rear frame structure is integrated with the front frame structure; the front supports are propped against the front frame structure of the seat from the lower side, so as to support the front frame structure from the lower side; the rear supports are propped against the rear frame structure of the seat from the lateral sides, so as to support the rear frame structure from the lateral sides.