The hybrid compressor apparatus is composed of a compressor in which fluid is compressed by varying a volumetric capacity of a compression space provided between a first compression member and a second compression member, which are movable independently of each other, according to rotation of the first compression member relative to the second compression member, a motor rotatable upon receipt of power of an external electric source, and a driven member rotatably driven by motive force transmitted from an external driving source. The first compression member is connected with the driven member and the second compressor is connected with the motor. If maximum discharge amount is required for the compressor, the motor is driven separately by a control device when the driven member drives the first compression member so that the second compression member is rotated in a direction opposite to that of the first compression member.