An optical transmission module that can be produced more easily and uses a shorter wiring pattern connecting the driving device and the light-emitting device than the conventional light-emitting apparatus, with the driving device and the light-emitting device arranged close to each other. The light-emitting device and the light-receiving device for monitoring the backward light emitted from the light-emitting device are arranged on a main surface of the substrate. The driving device is disposed on a bottom of a concave formed between the light-emitting device and the light-receiving device so that the driving device is lower than a straight line connecting a backward light emitting point of the light-emitting device and a backward light receiving point of the light-receiving device.