Objective: To investigate the effects of HPV16E6-ribozyme on telomerase activity in cervical carcinoma cell line CaSKi and the related mechanisms. Methods: Anti-HPV16E6-ribozyme and blank eucaryotic plasmids were transfected into CaSKi cells via lipofectin, and the resultant cells were named as CaSKi-R and CaSKi-P, respectively. The expression of ribozyme in transfected cells was observed by RNA dot blotting. The expression of E6 mRNA and protein in the 3 kinds of cells were detected by Northern blotting and Western blotting, respectively. Telomerase activity was determined by TRAP-Elisa method; the expression of P53, c-myc, hTERT and hRT mRNA were examined by RT-PCR.Results: RNA dot blotting showed that anti-HPV16E6-ribozyme was stably expressed in transfected CaSKi-R cells. Western blotting showed that the expression of E6 mRNA and protein in CaSKi-R cells was obviously lower than that in CaSKi and CaSKi-P cells. The telomerase activities in CaSKi,CaSKi-P and CaSKi-R cells were (0.89?0.14), (0.90?0.11) and(0.36?0.06),respectively. The inhibitory rate of telomerase activity in CaSKi-R cells was 59.55%, which was significantly lower than those in CaSKi and CaSKi-P cells (P