A light source device, comprising a first light source, a fly-eye lens pair, a light guiding system, and a wavelength conversion device; wherein the first light source is configured to emit first exciting light which is homogenized by the fly-eye lens pair and then incident to the light guiding system; the light guiding system comprises a first light splitting assembly, the first light splitting assembly is configured to guide the first exciting light to the wavelength conversion device; the wavelength conversion device comprises a wavelength conversion section and a reflective section and periodically moves in such a manner that the wavelength conversion section and the reflective section are periodically located on an optical path of the first exciting light in different time divisions, wherein the wavelength conversion section absorbs the first exciting light and emits excited light, and the first exciting light is obliquely incident to a surface of the reflective section and is reflected to form second exciting light; the light guiding system comprises a collecting lens, the collecting lens is configured to collect the excited light and the second exciting light to the first light splitting assembly, and the first light splitting assembly is configured to guide the excited light and the second exciting light to exit along an exiting light channel; and characterized in that the light guiding system further comprises an optical path correcting assembly (209, 209a, 209b, 209c, 209d) located on an optical path of the second exciting light and configured to reflect the second exciting light in such a manner that a main optical axis of the reflected second exciting light coincides with that of the excited light; and the fly-eye lens pair comprises a first lens array and a second lens array that are sequentially disposed along a direction of the first exciting light, wherein an optical axis of the first lens array is parallel to an optical axis of the second lens array, wherein the first lens array and the second lens array are respectively composed of a plurality of one-to-one corresponding lens units and a focus of a lens unit of the first lens array coincides with a center of a corresponding lens unit in the second lens array, so that lens units constituting the first lens array are configured to perform imaging with overlap on a surface of the wavelength conversion device. the first light source is configured to emit first exciting light which is homogenized by the fly-eye lens pair and then incident to the light guiding system; the light guiding system comprises a first light splitting assembly, the first light splitting assembly is configured to guide the first exciting light to the wavelength conversion device; the wavelength conversion device comprises a wavelength conversion section and a reflective section and periodically moves in such a manner that the wavelength conversion section and the reflective section are periodically located on an optical path of the first exciting light in different time divisions, wherein the wavelength conversion section absorbs the first exciting light and emits excited light, and the first exciting light is obliquely incident to a surface of the reflective section and is reflected to form second exciting light; the light guiding system comprises a collecting lens, the collecting lens is configured to collect the excited light and the second exciting light to the first light splitting assembly, and the first light splitting assembly is configured to guide the excited light and the second exciting light to exit along an exiting light channel; and characterized in that the light guiding system further comprises an optical path correcting assembly (209, 209a, 209b, 209c, 209d) located on an optical path of the second exciting light and configured to reflect the second exciting light in such a manner that a main optical axis of the reflected second exciting light coincides with that of the excited light; and the fly-eye lens pair comprises a first lens array and a second lens array that are sequentially disposed along a direction of the first exciting light, wherein an optical axis of the first lens array is parallel to an optical axis of the second lens array, wherein the first lens array and the second lens array are respectively composed of a plurality of one-to-one corresponding lens units and a focus of a lens unit of the first lens array coincides with a center of a corresponding lens unit in the second lens array, so that lens units constituting the first lens array are configured to perform imaging with overlap on a surface of the wavelength conversion device.