The present invention relates to a laminated heat exchanger having a laminated construction consisting of a plurality of perforated heat transfer plates and spacers arranged alternatingly, the spacers defining a plurality of fluid passages between respective adjacent heat transfer plates, so that heat is exchanged between different fluids flowing in different fluid passages through the heat transfer across the heat transfer plates. More specifically, the invention is concerned with a heat exchanger of the type described above, wherein a plurality of separate scroll passages are formed by the spacer, so that local concentration of each fluid in its passage is avoided to remarkably improve the heat transfer efficiency.