A parallel optical subassembly module structure comprises an opto-electronic device array, a base with a reflecting slope, and a micro-lens array plate with an inclined plane provided with a specific angle. The optical signal emitted from the opto-electronic device array reflects by the reflecting slope and is incident into the inclined plane of the micro-lens array plate with the specific angle. The inclined plane rectifies the optical signal to output in horizontal direction. Then the optical signal couples with the external fibers through each micro lens of the micro-lens array. The pathway of receiving the optical signal is the same as described above, but in reverse direction.