In the present study, we evaluated the efficacy of sildenafil and pentoxifylline combined therapy in the treatment of vasculogenic erectile dysfunction. Sixty-eight patients with various degrees and types of vasculogenic erectile dysfunction were included in the study. The patients were recommended to take oral sildenafil (minimum two 50-mg tablets/week) 1 h prior to sexual intercourse for 4 weeks. After 4 weeks of washout period, patients were recommended to take combined therapy (minimum two 50-mg tablets/week sildenafil 1 h prior to sexual intercourse and 1.2 g of pentoxifylline/day divided into three doses) for an additional 4-week period. Both treatment regimes were evaluated with the international index of erectile function (IIEF). Mean IIEF score was higher after sildenafil treatment when compared to pre-treatment score (14.2+/-4.3 and 8.6+/-4.2, respectively, P<0.05). Likewise after the combination treatment, mean IIEF score was higher when compared to pre-treatment score (18.1+/-5.2 and 8.6+/-3.8, respectively, P<0.05). The increase in the IIEF score was 5.62+/-2.08 in the sildenafil only group whereas increase in the IIEF score was 9.51+/-3.77 in the combination therapy group. There was a statistically significant increase in the combination group when compared to the sildenafil only group (P<0.001). Our study suggests that use of sildenafil citrate and pentoxifylline combined therapy could be effective in the management of patients with vasculogenic erectile dysfunction.