A photoelectric converting circuit including a light-receiving element which produces a current signal corresponding to the amount of light incident upon it and a current-to-voltage converting circuit which converts the current signal to a voltage signal. The circuit is characterized in that the current signal is supplied to the current-to-voltage converting circuit through an active circuit which exhibits a low input impedance. In preferred embodiments, the active circuit is a common-base transistor circuit in which an emitter current is supplied to the light-receiving element and a collector voltage is outputted as an output signal.
