According to the invention, a compressor having a threaded screw connection portion formed directly on a fitting portion of the housing is provided. Since no through bolt or the like for connecting two-parts of the housing is used, the diameter of the housing can be reduced. However, in a case that a suction port and discharge port do not align with an external mounting structure, a mounting means able to slide on the housing and adjust the positions of mounting brackets at least in the direction of rotation is added.