The present invention provides an optical transmitting module capable of outputting a signal for precisely controlling bias and modulation current, and a transmitting optical sub-assembly using the same. The optical transmitting module of the invention builds a semiconductor laser diode 5 and a temperature sensor within a CAN type package. The CAN type package includes a base, a block provided on the base and mounting the laser diode on a side thereof, and a plurality of leads secured to the base. The laser diode is supplied current signal S.sub.DRV through one of leads, while the temperature sensor outputs a signal S.sub.TEMP through the other of leads. The temperature sensor is mounted immediately close to the laser diode, accordingly, capable of monitoring the temperature of the laser diode.