Abstract: A cat house capable of being spliced includes: a side wall defining an accommodating space, and including a connecting hole communicating with the accommodating space, plural fixing holes surrounding the accommodating space, and plural inner corners facing the accommodating space, at least one of the inner corners is 120 degrees; a reinforcing plate disposed in the accommodating space and including plural positioning ribs inserted through the fixing holes, and one of the positioning ribs including a reinforcing hole; and a reinforcing pin inserted in the reinforcing hole in such a manner that the body section is located in the reinforcing hole, and the head section and the tail section are abutted against an outer surface of the side wall. Since the side walls of both a pentagonal cat house and a hexagonal cat house have 120-degree inner corners, the cat houses can be spliced to each other.