The purpose of this study was to evaluate the variance of apoptosis in rats in which experimental varicocele was induced and then treated by varicocelectomy. Forty adult male Wistar albino rats were used in this experimental study. Experimental varicocele was created in 30 rats. A total of 5 rats underwent a sham operation, and the remaining 5 rats were the control group. A total of 5 rats from the varicocele group were sacrificed on the 14th postoperative day, and 5 more were sacrificed on the 28th postoperative day to document the level of apoptosis due to varicocele. Varicocelectomy was performed on 20 rats with varicocele on the 14th postoperative day. These 20 rats were divided into 4 groups to evaluate the level of apoptosis in their testis after varicocelectomy. They were sacrificed on days 7, 14, 21, and 28 after varicocelectomy. The testes were fixated by perfusion with 10% formaldehyde and then placed in paraffin blocks. From each testis, 2 samples were stained with hematoxylin and eosin, and 2 samples were stained using the TUNEL method. In each specimen, apoptotic germ cells stained by TUNEL were counted in the cross section of 100 seminiferous tubules. The apoptotic index was defined by calculating the number of apoptotic cells per seminiferous tubule. Apoptotic index = total apoptotic germ cell count / 100. In the adult rats on which experimental varicocele was performed, both in the second and fourth week, apoptosis in both left and right testes were significantly higher compared with the control group (with varicocele day 14:0.25-0.26, with varicocele day 28:0.28-0.32, control: 0.11-0.13). After varicocelectomy on the 7th and 14th days, the slight increase in the level of apoptosis continued (day 7 left testis: 0.30, day 7 right testis: 028; day 14 left testis: 0.25, day 14 right testis: 0.31). After varicocelectomy, apoptosis decreased significantly on day 21 (left testis: 0.16, right testis: 0,22), and on day 28 it was almost equal to the level of the control group (left testis: 0.14, right testis: 0.16). After the creation of unilateral varicocele, the level of apoptosis increased in both the left and right testes. Apoptosis in both testes decreased after surgical treatment.