Objectire：To construct a recombinant lentivirus harboring RNAi sequence targeting rat nogo receptor gene and to observe its infection efficiency of 293T cells. Methods： Lentivirus shuttle plasmid containing siNgR199 cDNA was constructed by gene engineering and was used to transfect 293T cells in the presence of packaging plasmids. Forty-eight hours later the supernatant was collected and the titer of virus was determined. The recombinant lentivirus and the standard lentivirus were used to transfect 293T cells at 1 MOI,3 MOI,5 MOI, 10 MOI and 20 MOI. Polymerase chain reaction （PCR） was used to detect the recombinant vectort enhanced green fluorescent protein （EGFP） expression was used to determine the titer and the infection rate of the recombinant lentivirus under fluorescent microscope. Results： Restriction endonuclease and PCR analysis confirmed that the siNgR199 cDNA was successfully inserted into the lentivirus vector. The titer of the recombinant lentivirus harboring siNgR199 was 1 ×10^8 ifu/ml and the best MOI was 3. Conclusion- The recombinant lentivirus containing siNgR199 gene has been successfully constructed, which lays a foundation for future axon regeneration in treatment of spinal cord injury