Abstract: Due to the fast curing speed, high precision and smooth surface, UV-curing 3D printing has become one of the preferred technologies to rapidly manufacture sophisticated devices. However, the photosensitive resins for UV-curing 3D printing are still challenged by poor mechanical strength and toughness. Carbon fiber has been widely utilized in diverse structural or functional composites because of its excellent characteristics like electrical conductivity, heat conductivity, high specific strength and high specific modulus. Therefore, modified short carbon fiber (MCF) was prepared by chemical oxidation and modification with silane coupling agent (KH580). Then, the modified carbon fiber/photosensitive resin (MCF/PR) composite was prepared by compositing MCF with 3D printing photosensitive resin (PR). The UV-curing kinetics of MCF/PR composite and mechanical performances of 3D printed samples were also studied. The results indicate that when the grafted amount of KH580 is 0.5wt% and the content of MCF is 0.15wt%, the viscosity of MCF/PR composite is increased to some extent, but the curing depth and critical exposure are insignificantly influenced by MCF, which still meets the requirements of UV-curing 3D printing. A variety of devices are successfully fabricated by stereolithography (SLA) 3D printing. The tensile strength and impact strength of 3D printed samples are 70 MPa and 1.91 kJ/m², respectively, which are increased by about 100% and 60% compared with pure PR. Moreover, the 3D printed MCF/PR composite has good thermostability below 350℃.