This study compares the efficacy and safety of Tadalafil alone versus combined with Lidocaine topical spray in treating patients with coexisting Erectile Dysfunction (ED) and Premature Ejaculation (PE). Conducted from March to September 2023, the randomized controlled trial involved 98 patients. The International Index of Erectile Function (IIEF-5) and the Chinese Index of Premature Ejaculation Diagnostic Tool (CIPE-5) were used to assess changes before and after treatment. Results indicated that the combination therapy group showed significantly better improvement in PE symptoms than the Tadalafil alone group, while the improvement in ED was not significantly different between the two groups. The study suggests that for patients with coexisting ED and PE, the combined use of Tadalafil and Lidocaine spray might be a more effective treatment strategy.