The present invention provides an optical transceiver with an optical subassembly optically coupling with an optical connector via a receptacle member, in which the optical subassembly is positioned to the housing of the transceiver without causing any mechanical stress. The optical subassembly is fixed to the receptacle member by inserting a sleeve thereof into an opening of the receptacle member. The receptacle member is assembled with the housing via the holder by adjusting the positional relation between the holder and the housing. Therefore, even when the subassembly is fixed to the receptacle member via the sleeve thereof, the subassembly can fit to the housing without causing any mechanical stress because the holder is interposed therebetween, which secures the heat dissipating path from the optical subassembly to the housing.