Introduction. The volumetric predominance of one testis over the other, also known as testicular asymmetry, has been proposed as a prognostic factor for varicocele repair, with a cutoff for the significance of 20%, and for the evaluation of the functional capacity of small testes, particularly in patients with a history of cryptorchidism. At the same time, we commonly see patients whose right testicle is to varying degrees smaller as the left testicle. Methods. The study included 64 patients with idiopathic sever OAT syndrome which were evaluated for: testicular volume, using testicular volume were calculated Testicular Asymmetry Ratio (TAR= Right Testicular Volume/Left Testicular Volume) and were corelated with the semen parameters. Results. Following data analysis, 32 (50%) of the 64 patients with severe OAT syndrome of unknown cause were found to have TAR 1, 19 (29.7%) to have TAR=1–1,2, and 13 (20.3%) to have TAR>1.2. For TAR1,0, the median values were 0.86 [0.75-0.92], for TAR=11,2, the median values were 1.07 [1.05-1.12], and for TAR>1,2, values were 1.33 [1.25-1.49]. This points out that individuals with significant RT pathologic asymmetry have higher TV than individuals with large LT pathologic asymmetry. In the instance of lower RTV linked with TAR 1,0 the mean volume was higher than mean LTV with TAR > 1,2. Conclusions. According to observations, males whose right testicle is smaller in volume than their left testicle frequently have substantial changes in the quality of their semen. We might conclude that lower RTV can have a greater impact on overall fertility than lower LTV given that all individuals included in the study had nearly identical semen outcomes.