Semiconductor single walled carbon nanotubes (s-SWCNTs) is one of the most promising channel materials for the next generation of field effect transistors and integrated circuits. The length of s-SWCNTs is shortened during dispersion and separation. The existence of many ultra-short tubes with length less than 100 nm will increase the lap resistance between tubes and increase the scattering probability of carriers, which will lead to the degradation of device performance. It is not beneficial to the development and application of high-performance carbon nanotube devices. However, there is still a lack of research on the separation of s-SWCNTs length in organic system, especially the controllable removal of ultra-short tubes. In this paper, we developed a silica gel adsorption technology in organic system, which successfully achieved the efficient removal of ultra-short carbon nanotubes and effectively regulated the length distribution of semiconductor carbon nanotubes. The on-state current and maximum transconductance of the transistors prepared by the CNTs with length-sorted are 8.9 μA/μm and 0.5 mS/μm, which are about 300% and 250% higher than those of the device without length-sorted, respectively.