The invention discloses a novel self-locking tree support. The novel self-locking tree support comprises a fixing base, supporting rods, adjusting rods and an elastic binding band; a plurality of supporting pieces are uniformly arranged on the elastic binding band, a sliding way is formed in each supporting rod, and the fixing base is of an annulus structure; the top and the bottom of each supporting rod are connected with a bolt hole in the corresponding supporting piece and a bolt hole in the fixing base, a self-locking unit is arranged at the bottom of each adjusting rod, each self-locking unit comprises a gear, a gear lock and a gear holder, wherein the gear is rotationally arranged on the gear holder, the gear lock comprises a locking plate, a physical pendulum and a suspension bracket, the locking plate, the physical pendulum and the suspension bracket are arranged on the gear holder, the locking plate is rotationally connected with the suspension bracket, a groove is formed in the lower surface of the locking plate, a top plate is rotationally arranged on the suspension bracket, and one oblique plane is arranged on the side, away from the suspension bracket, of the upper surface of the top plate. When used, the novel self-locking tree support can be automatically suitable for the changes of the diameter of a tree according to the growth of the tree, and meanwhile, a strengthening effect on the tree can be achieved.