Sub-diffraction-limit fabrication of 6H-SiC is investigated with femtosecond laser direct-write setup. Micro/nano-fabrication on 6H-SiC is studied with a home-made micro/nano-fabrication platform, which is integrated with a fluorescence microscope and a Ti:sapphire laser with a central wavelength of 800 nm and pulse duration of 130 fs. Micro/nano-structures are characterized with scanning electron microscope. It is found that the spatial resolution is improved with the decrease of laser power and the increase of scanning velocity. The smallest resolution achieved is 125 nm and line array with a line width of 240 nm and a period of 1 μm is fabricated. This work paves the new way for integrated micro electro-mechanical systems devices.