PROBLEM TO BE SOLVED: To provide an illuminating device which can control a light amount into a target light amount with high accuracy without losing the balance in an outgoing light amount ratio among a plurality of semiconductor light sources, and to provide an endoscope apparatus equipped with the illuminating device.SOLUTION: An illuminating device comprises: a plurality of semiconductor light sources emitting light of different spectra target light amount setting means setting a target light amount with respect to a total outgoing light amount light amount ratio setting means which sets outgoing light amount ratio of the plurality of semiconductor light sources amplitude value setting means setting each amplitude value of a driving signal for each of the semiconductor light sources on the basis of the set outgoing light amount ratio and drive signal generation means generating each driving signal by common pulse modulation control corresponding to a target light amount while holding the set amplitude value. When a target light amount is set, a driving pulse signal corresponding to the target light amount is set commonly to the respective semiconductor light sources, the driving pulse signal is made to be an amplitude value corresponding to the outgoing light amount ratio, and individual driving signals driving the respective semiconductor light sources are generated.SELECTED DRAWING: Figure 1
