Objective: To determine whether combined pentoxifylline (PTX) and tocopherol (vitamin E) treatment can improve clinical pregnancy and endometrial thickness. Materials and Methods: One hundred twelve infertile women undergoing standardized controlled ovarian hyper stimulation for ICSI- ZIFT entered this randomized clinical trial. Patients were randomized to two groups of combined drug therapy or none. Pentoxifylline 400 mg/BD plus vitamin E 400 mg/BD were administered to the intervention group for two cycles before starting ICSI/ZIFT cycle until detecting positive beta-hCG or the cycle was cancelled. The other group did not receive combination drug therapy. Main outcome measures were clinical pregnancy and endometrial thickness. Results: The clinical pregnancy was higher in the intervension group in comparison to the other group (57.14% vs 39.29%, p=0.01). However, there was no difference in the mean endometrial thickness, number of retrieved oocytes, the number of metaphase 2 oocytes and grade of them in both groups. Conclusion: This study showed that Pentoxifylline plus vitamin E could improve the ZIFT outcome in infertile couples. Local effects and antioxidative characteristics of these drugs may be the cause of better results.