Abstract: The present invention provides an optical receiver that suppresses the saturation in the output without alleviating the bandwidth restriction of the current-to-voltage conversion gain. This optical receiver comprises an amplifier 4 for receiving a photocurrent IIN from a photodiode, and a plurality of trans-impedance elements connected in parallel between the input terminal and the output terminal of the amplifier 4. One trans-impedance element includes only resistor, while the other trans-impedance elements include semiconductor switches and resistors connected in series to the semiconductor switches so as to put the semiconductor switches therebetween.