A support, comprising: a seat body, on which a receiving slot is provided; a support foot provided on the seat body and rotatable relative to the seat body, the support foot being configured to be extended to support the seat body or to be folded for being received in the receiving slot; and a locking structure provided on the seat body for locking the support foot to support the seat body atter the support toot is extended, or for unlocking the support toot to enable the support toot to be received when the support toot is folded, wherein a holding structure adapted to the support foot is provided in the receiving slot for preventing the support foot from detaching from the receiving slot after being stored, wherein the holding structure comprises: a first block disposed on an inner wall of the receiving slot; and a second block disposed on the inner wall of the receiving slot and symmetrically arranged with the first block for cooperating with the first block to latch the support foot in the receiving slot, and characterized in that the locking structure is a locking ring and a retaining slot is provided on the seat body, wherein the locking ring comprises: a ring body rotatably mounted in the seat body; a baffle affixed to the ring body and simultaneously rotatable with the ring body for locking the support foot when the support foot is extended or for unlocking the support foot when the support foot is folded, and a rod, wherein one end of the rod is fixedly assembled with the ring body and the other end of the rod is movably accommodated in the retaining slot for driving the ring body to rotate to drive the baffle to rotate. a seat body, on which a receiving slot is provided; a support foot provided on the seat body and rotatable relative to the seat body, the support foot being configured to be extended to support the seat body or to be folded for being received in the receiving slot; and a locking structure provided on the seat body for locking the support foot to support the seat body atter the support toot is extended, or for unlocking the support toot to enable the support toot to be received when the support toot is folded, wherein a holding structure adapted to the support foot is provided in the receiving slot for preventing the support foot from detaching from the receiving slot after being stored, wherein the holding structure comprises: a first block disposed on an inner wall of the receiving slot; and a second block disposed on the inner wall of the receiving slot and symmetrically arranged with the first block for cooperating with the first block to latch the support foot in the receiving slot, and characterized in that the locking structure is a locking ring and a retaining slot is provided on the seat body, wherein the locking ring comprises: a ring body rotatably mounted in the seat body; a baffle affixed to the ring body and simultaneously rotatable with the ring body for locking the support foot when the support foot is extended or for unlocking the support foot when the support foot is folded, and a rod, wherein one end of the rod is fixedly assembled with the ring body and the other end of the rod is movably accommodated in the retaining slot for driving the ring body to rotate to drive the baffle to rotate. a first block disposed on an inner wall of the receiving slot; and a second block disposed on the inner wall of the receiving slot and symmetrically arranged with the first block for cooperating with the first block to latch the support foot in the receiving slot, and characterized in that the locking structure is a locking ring and a retaining slot is provided on the seat body, wherein the locking ring comprises: a ring body rotatably mounted in the seat body; a baffle affixed to the ring body and simultaneously rotatable with the ring body for locking the support foot when the support foot is extended or for unlocking the support foot when the support foot is folded, and a rod, wherein one end of the rod is fixedly assembled with the ring body and the other end of the rod is movably accommodated in the retaining slot for driving the ring body to rotate to drive the baffle to rotate. a ring body rotatably mounted in the seat body; a baffle affixed to the ring body and simultaneously rotatable with the ring body for locking the support foot when the support foot is extended or for unlocking the support foot when the support foot is folded, and a rod, wherein one end of the rod is fixedly assembled with the ring body and the other end of the rod is movably accommodated in the retaining slot for driving the ring body to rotate to drive the baffle to rotate.