A coupling structure for vehicle chassis members couples a ball joint member and an axle housing used for a vehicle to each other. The structure includes a socket that has a substantially columnar external shape, is provided in the ball joint member, and has a socket bolt groove throughout a circumference in an outer circumferential surface of the socket. The structure also includes a collar that has a substantially cylindrical shape and is disposed so as to surround an outer circumferential surface of the socket. The axle housing has a coupling hole having a substantially columnar internal shape into which the socket is inserted. The ball joint member and the axle housing are coupled to each other by disposing the socket in the coupling hole while the socket is surrounded by the collar.