Waist support capable of being self-locked and overturned

The utility model discloses a waist support capable of self-locking and overturning, which comprises a locking fastener and a buckle sleeve which is used for being rotatably connected with a cross rod of a seat, the locking fastener and the buckle sleeve are coaxially arranged, and the locking fastener axially slides along the cross rod to be used for being connected with the buckle sleeve in an abutting or non-contact manner. An elastic component is fixedly arranged in the locking fastener and is fixedly connected with the cross rod; the waist support is arranged on the seat and can be matched with the seat to be folded, normal use of the unfolded seat is not affected, the waist support is provided with the connector capable of achieving self-locking and free rotation, the connector is arranged on the upper cross rod of the seat, the two limiting components only need to be moved outwards by hands when folding is needed, operation is simple, and the folding effect is good. The waist support can turn over rela