To provide a plate type heat exchanger for an evaporator that improves heat exchange efficiency by preventing a partial increase of liquid mist of a refrigerant in a part in a housing and effectively working all heat transfer surfaces.

The plate type heat exchanger 1X for an evaporator comprises the housing 13 having a refrigerant inlet 11 and a refrigerant outlet 12, and a plurality of hollow plates 14 arranged in the housing to divide the internal space of the housing 13 into a plurality of small passages 15 that deflect a refrigerant from the refrigerant inlet 11 to the refrigerant outlet 12, to form passages for a cooled fluid separated from the refrigerant and to form heat transfer surfaces for transferring heat from the refrigerant. Thin tubes 2A to 2C and a through-hole 3 are provided to divert a refrigerant from the refrigerant inlet 11 into a plurality of passages and individually lead it in an evenly dispersed manner from a position near the refrigerant inlet 11 to a spaced position in a space portion 16 on an inlet side of the small passages 15.