OBJECTIVE: To evaluate the efficacy of tadalafil half-dose (10 mg) taken orally every other day for the treatment of ED. METHODS: 158 ED patients who met the diagnostic criteria of the National Institutes of Health (NIH) were selected and randomly divided into two groups, the tadalafil group and the compound Xuanjiao capsule group, to receive 3 months of treatment, and then each group was followed up for more than 3 months after treatment. Erectile dysfunction symptom score (internationalindexoferectilefunction-5,IIEF-5) was used to assess the efficacy of each group before and after treatment and after 3 months of follow-up, and to compare the success rate of insertion in the patients’ sexual life diary and the success rate of maintaining erection until completion of sexual intercourse during sexual intercourse. The self-ratinganxietyscale (SAS) was used to evaluate the anxiety status. RESULTS: The IIEF-5 scores of the two groups before treatment were (9.96±4.21) and (9.69±4.35), respectively, with no statistically significant difference (P＞0.05), and the IIEF-5 scores after 3 months of treatment were (20.38±4.18) and (16.08±3.26), respectively, and the IIEF-5 scores at the follow-up to 6 months were ( 18.16±2.31) and (11.98±3.97) points, the differences were statistically significant (P<0.01), and the differences in scores between the two groups at post-treatment and 6-month follow-up were also statistically significant (P<0.05).After drug treatment, the success rate of insertion in the patients' sexual diary and the success rate of maintaining erection were significantly higher in the tadalafil group than in the compound Xuanjiao capsule group . Anxiety score values were significantly lower in both groups after treatment than before treatment (P < 0.05). CONCLUSION: Tadalafil taken orally in half doses every other day can effectively treat ED, and its efficacy is better than that of traditional Chinese medicine, so it can be used as the first-line treatment in clinic.