Assembly type convenient-to-install composite structural slab

The invention belongs to the technical field of building materials, and discloses an assembly type convenient-to-install composite structural slab. The slab includes an inner frame which is shaped bya cold-formed steel strip, the inner frame is filled with cementitious materials, the side edges of the inner frame are provided several first connection holes, one side edge of the inner frame is provided with a connection convex block, and the other side edge of the inner frame is provided with a connection groove. The connection convex block and the connection groove are both provided with elongated slots in which waterproof rubber belts are placed, and the first connection holes are provided with reserved holes facilitating the installation of fasteners. The slab can overcome the shortcoming of insufficient compactness between common wallboards and can meet the rigid requirements of the waterproof quality, the heat preservation quality and the like in construction engineering. Meanwhile, the problem of joint c