A fastening system for fastening an electronic device (2) in a measurement housing (1), comprising: an electronic-device holder (10) designed to accommodate an electronic measurement device (2); and a prestressing ring (20) that is able to cooperate with said holder (10) for assembly and comprises a plurality of prestressing beams (22, 25) designed to bear on said electronic device (2) when said ring is assembled together with the holder, said electronic device (2) being inserted into said holder (10).