Objective:To investigate the effects of ICSI(intracytoplasmic sperm injection)cycles with frozen sperm obtained by PESA(percutaneous epididymal sperm aspiration)by retrospective study performed in 54 patients. Methods:Sperm from the 54 infertile males by PESA were frozen with conventional freezing method. After frozen-thawed and ICSI process,the fertilized oocytes were cultured in vitro for 72 hours and high quality embryos were transfered to the wives. 282 cases of fresh epidielymal sperms were tested as control. Fertilization rate,implantation rate,clinical pregnancy rate were compared beween two groups,the cycle with frozen-thawed sperm and the cycles with fresh PESA sperm as control. Results:No significant differences were found in rate of fertilization,cleavage high-qualified embryo,clinical pregnancy between two groups(72.4% vs 74%,98.1% vs 96.3%,51.7% vs 46.8%,42.6% vs 39.0%,respectively,P > 0.05). Neither vital pregnant complications nor neonate malformations were found in both groups. Recovering rate of frozen sperm form PESA was 65.9%. Conclusion:The embryo development and pregnant outcome were not effected by using frozen-thawed sperm obtained by PESA.