A four-way valve of simple structure that even in the flow of high-temperature refrigerant and low-temperature refrigerant in close vicinity of each other, inhibits the occurrence of any heat loss due to heat leakage therebetween. There is provided a four-way valve comprising housing member (5) furnished with valve chest (51); valve seat (6) having seat surface portion (61) disposed in the valve chest (51); second flow channel (2) for passage of low-temperature fluid and first flow channel (1) for passage of high-temperature fluid at given timing both drawn outside the valve chest (51) through the valve seat (6), the first flow channel (1) and second flow channel (2) having respective openings (1a,2a) adjacent to each other at the seat surface portion (61) of the valve seat (6); and valvebody (7) disposed in a fashion movable on the seat surface portion (61) of the valve seat (6), wherein between the first flow channel (1) and second flow channel (2) at position close to the openings(1a,2a), there is disposed thermal resistance part (8) capable of inhibiting any heat transfer between these flow channels.