A micro channel type heat exchanger having a first pass disposed in some flat tubes located in a first heat exchange module and along which a refrigerant flows in one direction, a second pass disposed in some of the remaining flat tubes located in the first heat exchange module and along which the refrigerant supplied from the first pass flows in an opposite direction to that of the first pass, a third pass distributed and located in the remainder of flat tubes located in the first heat exchange module other than the first pass and the second pass and in some flat tubes located in a second heat exchange module, and a fourth pass disposed in the remainder of the flat tubes located in the second heat exchange module and along which a refrigerant supplied from the third pass flows in an opposite direction to a direction of the third pass.