A light source device for irradiating a target with light, comprising: a light source which emits light to be irradiated, a chromaticity measurement part for measuring the chromaticity of the emitted light emitted by the light source, a chromaticity adjustment part capable of placing/removing a chromaticity adjustment-use filter (CHA, CHB) onto/from the light path of the emitted light and capable of adjusting the chromaticity of the emitted light by placement/removal of the chromaticity adjustment-use filter (CHA, CHB), and a control part which monitors a change of the chromaticity of the emitted light according to the results of measurement of the chromaticity measurement part and controls placement/removal of the chromaticity adjustment-use filter (CHA, CHB) of the chromaticity adjustment part onto/from the light path so that the chromaticity becomes the chromaticity which is set in advance as a target, whereby the chromaticity adjustment part can place/remove two different types of filters of a first chromaticity adjustment-use filter and second chromaticity adjustment-use filter onto/from the light path of the emitted light, through which the emitted light can be transmitted, and the control part individually controls the amounts of insertion of the first chromaticity adjustment-use filter and the second chromaticity adjustment-use filter onto the light path, whereby the control part comprises a filter driver for controlling placement/removal of the first chromaticity adjustment-use filter and second chromaticity adjustment-use filter in the chromaticity adjustment part onto/from the light path, the filter driver being configured to allow setting the amount of insertion of the first chromaticity adjustment-use filter to zero and the second chromaticity adjustment-use filter to zero, whereby the first and second chromaticity adjustment-use filters (CHA, CHB) are not inserted onto the light path. a light source which emits light to be irradiated, a chromaticity measurement part for measuring the chromaticity of the emitted light emitted by the light source, a chromaticity adjustment part capable of placing/removing a chromaticity adjustment-use filter (CHA, CHB) onto/from the light path of the emitted light and capable of adjusting the chromaticity of the emitted light by placement/removal of the chromaticity adjustment-use filter (CHA, CHB), and a control part which monitors a change of the chromaticity of the emitted light according to the results of measurement of the chromaticity measurement part and controls placement/removal of the chromaticity adjustment-use filter (CHA, CHB) of the chromaticity adjustment part onto/from the light path so that the chromaticity becomes the chromaticity which is set in advance as a target, whereby the chromaticity adjustment part can place/remove two different types of filters of a first chromaticity adjustment-use filter and second chromaticity adjustment-use filter onto/from the light path of the emitted light, through which the emitted light can be transmitted, and the control part individually controls the amounts of insertion of the first chromaticity adjustment-use filter and the second chromaticity adjustment-use filter onto the light path, whereby the control part comprises a filter driver for controlling placement/removal of the first chromaticity adjustment-use filter and second chromaticity adjustment-use filter in the chromaticity adjustment part onto/from the light path, the filter driver being configured to allow setting the amount of insertion of the first chromaticity adjustment-use filter to zero and the second chromaticity adjustment-use filter to zero, whereby the first and second chromaticity adjustment-use filters (CHA, CHB) are not inserted onto the light path.