The invention relates to a light source system comprising a blue LD light source group, a beam splitting device, a fluorescent color wheel, a first drive device, a beam combining device, a filter color wheel, and a second drive device. The beam splitting device is used for transmitting blue light and reflecting colored light newly generated by the fluorescent color wheel. The fluorescent color wheel comprises at least three regions which are distributed along the center axis of the fluorescent color wheel, do not overlap, and are shaped like a fan ring, wherein the at least three regions comprise a first region for transmitting blue light, a second region for converting the blue light into red light, and a third region for converting the blue light into green light. The first drive device is used for driving the fluorescent color wheel to rotate along the center axis of the fluorescent color wheel. The beam combining device is used for combining colored light emitted by the fluorescent color wheel. The filter color wheel is used for selecting colored light in a time-sharing manner. The second drive device is used for driving the filter color wheel to rotate along the center axis of the filter color wheel so as to make the fluorescent color wheel and the filter color wheel rotate synchronously. Through the above method, the light source system provided by the invention can improve the color saturation and color gamut of a light source so as to improve the display quality of a picture displayed through projection.