Aim:The aim of the study was to assess the efficacy of adding L-carnitine to clomiphene citrate for increasing the ovulation and the pregnancy rate in women with PCOS. The primary outcome was the ovulation rate and the secondary outcome was the pregnancy rate. Materials and Methods: This study was a randomized controlled clinical trial that was conducted on 94 women who attended at the Obstetrics and Gynecology Outpatient Infertility Clinic at Ain-Shams University Maternity Hospital, and they were diagnosed with PCOS according to the Rotterdam Criteria (11). The women were distributed randomly into two equal groups; Group L (n=47) received 100 mg of clomiphene citrate plus 3 gm of L-carnitine orally from day 3 to day 7 of the cycle with continuation of L-carnitine till the day of pregnancy test and Group C (n=47) received 100 mg of clomiphene citrate orally from day 3 to day 7 of the cycle. Results: There was a significant difference (P<0.05) between the two groups regarding the ovulation rate (Group L: 70.2%; Group C: 44.7%). There was no significant difference (P>0.05) between the two groups regarding the pregnancy rate (Group L: 8.5%; Group C: 6.4%). There was a highly significant difference (P<0.01) between the two groups as regards to the number of mature follicles (Group L: 1.6 ± 1.2; Group C: 0.8 ± 0.7), the days needed till hCG injection (Group L: 12.2 ± 1.5; Group C: 14.0 ± 1.8), the Endometrial thickness (Group L: 10.4 ± 1.2 mm; Group C: 9.1 ± 0.8 mm). There was no significant difference (P>0.05) between the two groups regarding the level of progesterone after 8 days from the hCG injection. Conclusion: L-carnitine added to clomiphene citrate for induction of ovulation in PCOS women had a significant effect on the ovulation rate, but it didn't have a significant effect on the pregnancy rate when compared to clomiphene citrate alone.