The invention relates to the technical field of baby carriages and particularly discloses a folding baby carriage. The folding baby carriage comprises a transitional frame, a handrail frame hinged to one end of the transitional frame, a front wheel carrier and a rear wheel carrier, wherein the front wheel carrier and the rear wheel carrier are hinged to the other end of the transitional frame. The handrail frame is connected with a first telescopic assembly in a sliding manner, and the transitional frame is connected with a second telescopic assembly in a sliding manner. One end of the second telescopic assembly protrudes and extends into the handrail frame. The first telescopic assembly is used for abutting against the second telescopic assembly. The second telescopic assembly is used for clamping the front wheel carrier and the rear wheel carrier. When the folding baby carriage needs to be folded, a user slides the first telescopic assembly to make the first telescopic assembly squeeze the second telescopic assembly, and the second telescopic assembly is squeezed out of the handrail frame. After the second telescopic assembly retracts out of the handrail frame, the second telescopic assembly does not clamp the handrail frame, the front wheel carrier and the rear wheel carrier any more, the user can fold the handrail frame, the front wheel carrier and the rear wheel carrier on the transitional frame, and therefore the whole baby carriage is folded. The folding baby carriage can be quickly folded and can be conveniently placed by the user.