The invention provides a light source system which comprises a light source master control module, a light-emitting device driving circuit, an optical fiber coupling component, a photoelectric detection component, bundling optical fibers and a bundling optical fiber terminal. The light intensity, detected by the photoelectric detection component, of light emitted by a light-emitting device is converted into electric signals to be transmitted to the light source master control module, when the output light strength deviates from a reference value by a certain scope, the output current or voltage of the light-emitting device driving circuit is automatically adjusted through the light source master control module, the intensity of the light emitted by the light-emitting device is maintained within the certain scope of the reference value all the time, and finally the constant light source output light power is guaranteed. The structure that a circular lens is combined with a cylindrical lens installed in a bundling optical fiber terminal protective sleeve and is adopted for the optical fiber coupling component, the surface of the cylindrical lens is coated with a reflection coating, the light emitted by the light-emitting device inside a light source main body is converged and averaged, an air curtain device is installed at the bundling optical fiber terminal to control compressed air to flow through a lens face of the cylindrical lens, and the aim of real-time cleaning on the lens face of the cylindrical lens is achieved.