Abstract: Objective 　To investigate the effects of peptide nucieic acid stargeting Ki67 gene ( PNAs) on the proliferation and apoptosis of human renal carcinoma cell line cells. Methods 　Human renal carcinoma cell line 786-0 cells were t reated with PNAs (10. 0μmol/ L) . The Ki67 expression of 786-0 cells was detected by immunohistochemical technique and Western blot method respectively. The proliferation of 786-0 cells was studied by cell growth curves and 3>> H-thymidinuptake assay. The apoptosis of 786-0 cells was detected by TUNEL assay. The cont ral group was t reated with antisense oligonucleotides (ASODNs) of Ki67. Results 　The Ki67 experssion rate of 786-0 cells t reated by PNAs (16. 9 ±0. 7) was lower than that of ASODNs t reated group (28. 6 ±0. 4) ( P < 0. 01) . The Ki67 protein rate of 78620 cells t reated by PNAs (42. 1 ±2. 2) was lower than that of ASODNs t reated group (83. 6 ±1. 4) ( P < 0. 01) . The 3 >>H-thymidine incorporation rates of 78620 cells t reated by PNAs (20. 7 ±1. 5) was lower than that of ASODNs t reated group (58. 6 ±1. 4) ( P < 0. 01) . The apoptosis rate of 786-0 cells t reated by PNAs (28. 7 ±2. 3) was higher than that of ASODNs treated group (13. 8 ±1. 0) ( P < 0. 01) . Conclusion 　PNAs have both antisense and antigene effcct s. PNAs of Ki67 have more powerful effect s on the proliferation and apoptosis of human renal carcinoma cells than ASODNs of Ki67 gene.