To provide a thin and compact electric circuit element block.

In a block of electric circuit elements 12 pressure-bonded and fixed to a plate-like heat sink 11 through retaining spring members 15, the elements 12 are disposed on a main flat face 11A of the heat sink 11 and guide pins 19A integrated with a fixing member 16 having cotter pins 20A coupled with coupling holes formed through the sink 11 are passed through guide holes 12B of the elements 12 whereby the elements 12 are positioned and held on the main face 11A and pressed to this face by the spring members 15, together with the fixing member 16.