To reduce the cost and the work man-hour and improve the heat exchange efficiency and the heat transfer ratio by eliminating the need of the conventional corrugated fins in a laminated heat exchanger composed of laminated tube elements, and avoid reducing the assembling or soldering workability of the tube elements to avoid lowering the strength between the tube elements.

Louvers 16 projecting outwards from a tube element 2 are formed integrally with a plate 6 constituting the tube element 2 at positions not interfering with passage forming recesses 8 for forming fluid passages. The louvers 16 can be substituted for the conventional corrugated fins, thereby increasing the heat exchanging area.