The invention discloses a large-view-field large-relative-aperture solar blind ultraviolet optical system. The system is formed by combining thirteen lenses and one ultraviolet narrowband optical filter and is sequentially composed of the first lens with positive focal power, the second lens with negative focal power, the third lens with negative focal power, the fourth lens with positive focal power, the fifth lens with positive focal power, the sixth lens with negative focal power, the seventh lens with positive focal power, an aperture diaphragm, the eighth lens with negative focal power, the ninth lens with positive focal power, the tenth lens with negative focal power, the eleventh focal power with positive focal power, the twelfth lens with positive focal power, the ultraviolet narrowband optical filter, the thirteenth lens with positive focal power and a focal plane detector from an object side to an image side. The work waveband is 260-280nm, F/# is 1.5, the focal length is 7.99mm, the view field is 75.2 degrees, and the length of the whole optical system is 157mm. The optical system realizes high illumination uniformity which is higher than 81.6%, improves the image quality by use of three aspheric surfaces and enables the total optical path lens of the optical system to be shorter. Through overall system movement, the system maintains high-quality imaging within a temperature scope from -40 DEG C to 60 DEG C.