Stair corner connector assembly

The utility model discloses a stair corner joint assembly, which belongs to the technical field of stairs, and comprises a main body box, a box cover arranged at the bottom of the main body box, a supporting mechanism arranged at the bottom of the box cover, and six cylinders arranged at the bottom of the supporting mechanism, the supporting mechanism comprises two first supporting plates, two connecting rods and two second supporting plates, the surfaces of the second supporting plates are sleeved with the first supporting plates, and the opposite sides of the two first supporting plates and the two second supporting plates are fixedly connected with the two connecting rods correspondingly. The problems that in the prior art, generally, wood sticks are directly used for supporting, stair corner connector assemblies are placed on the tops of the wood sticks, the wood sticks are taken down until stairs are built, and when the wood sticks are used for supporting, the supporting points of the multiple wood stick