A burst mode optical transmitter circuit comprises a semiconductor laser, a photodiode for monitoring the light output from the semiconductor laser, a current-voltage converting circuit for converting the current detected by the photodiode into a voltage, an APC amplifier, a holding circuit for holding, as a current control signal, the output signal from the APC amplifier, a driving circuit for supplying a driving current to the semiconductor laser according the current control signal from the holding circuit and the the data input in the burst mode, and a data interruption detecting circuit for detecting an interrupt period of the data input to the driving circuit to reset the holding circuit, in which the current control signal held in the hold circuit is reset by the reset signal, whereby a stable burst optical transmission can be performed stably with a simple construction.