An electronic circuit apparatus for a compressor includes a board and a case. One corner of the board is fixed to case such that the board cannot move in the thickness direction and is movable in the flattening direction. According to this structure, even when an electronic part generates heat or outside air temperature of the case varies, the expansion or contraction of the board in the flattening direction is not affected by the expansion or contraction of the case in the flattening direction. Therefore, it is possible to prevent the deformation of the board and stress from being repeatedly applied to a soldering portion of the electronic part. As a result, it is possible to ensure the reliability of soldering strength for a long time.