Background: The use of antibiotic prophylaxis during Lichtenstein inguinal hernia surgery is controversial, and no definitive guidelines are available in literature. Objective: To determine effects of prophylactic antibiotics in reducing the frequency of postoperative wound infection in Lichtenstein hernia repair. Study Design: Case control study. Setting: Surgical Unit II, Allied Hospital, Faisalabad.Duration: One year, between January 2007 and December 2007. Methods: Patients undergoing unilateral, primary inguinal hernia repair electively with the Lichtenstein technique using polypropylene mesh were randomized to receive 1.0 g intravenous Cefazolin before the incision or an equal volume of placebo. Wound infection was defined according to the criteria of Centers for Disease Control and recorded. Results wereassessed using chi-square test. Results: 100 patients were included in the study. Minimum age of patients in this study was 20 and maximum 75 years with a mean of 44.06 in group A and 44.84 in group B. The total number of wound infections was 7 (7%); 2 (4%) in the antibiotic prophylaxis group and 5 (10%) in the placebo group. Statistical analysis showed no significant difference in the number of wound infections inboth groups (p value=0.240). Conclusions: We conclude that in Lichtenstein inguinal hernia repair routine use of prophylactic antibiotics is not needed, as it does not significantly reduce the postoperative wound infection rates.