Background:Lichtenstein tension free repair of inguinal hernia a very effective repair but fibrosis generated around the mesh prosthesis may be hazardous to the vas deference and testicular blood supply thus impairing testicular function especially if done on both sides. Patient and methods:78 patients with bilateral inguinal hernia recruited in this prospective trial for evaluation of the effect of bilateral Lichtenstein tension free repair of inguinal hernia on testicular function we held comparison between preoperative and 6 months postoperative findings of; testicular volume, testicular blood flow (resistive index) semen analysis and free testosterone level as primary outcome and surgical site occurrences and recurrence rate as secondary outcome. Results: mean Age, BMI, Operative time were 33.1± 8.8 years , 27.6± 3.1, and 98.4±11.4 respectively, majority of hernia presentation was indirect hernia, we got 2 cases of chronic pain, one case of hydrocele and no recurrences, regarding testicular volume, resistive index, semen analysis and testosterone level noticed non-significant differences between pre and post repair results. Conclusion:In regard to testicular function, bilateral Lichtenstein tension free repair of inguinal hernia is an effective safe method, especially if laparoscopic repair is not available.