Ethnopharmacological relevance: Huoxue Tongluo Qiwei Decoction is a classical herbal formula, which can improve the symptoms of erectile dysfunction (ED) patients and has a good therapeutic effect on patients with diabetic erectile dysfunction (DIED). The main function of Huoxue Tongluo Qiwei Decoction is to stimulate the blood circulation and dredge collaterals, remove blood stasis, and calm wind. Rationale: To further explore the mechanism of Huoxue Tongluo Qiwei Decoction in the treatment of DIED, related animal experiments were designed. Materials and methods: The chemical constituents of Huoxue Tongluo Qiwei Decoction were identified with the help of high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). A rat model was induced by streptozotocin (STZ) and screened by apomorphine (APO). Serum sE-selectin, lysyl oxidase-1 (LOX1), malondialdehyde (MDA) and other markers of vascular endothelial injury and related indicators of oxidative stress were studied through enzyme-linked immunosorbent assay (ELISA). The endothelial cells and ultrastructure of the corpus cavernosum were examined by electron microscopy and HE staining. The expression of protein and mRNA was detected by western blotting (WB) and real-time quantitative polymerase chain reaction (RTqPCR). Results: The results of the study revealed that the sE-selectin, LOX-1, intercellular adhesion molecule-1 (sICAM1), endothelial microparticles (EMPs), P-selectin (CD62P), and MDA levels in the serum of group M rats were considerably higher than rats of group K, while the superoxide dismutase (SOD) level showed a significant decrease. In addition, the PKC pathway was activated, and the expression of related proteins and mRNA was increased. After 8 weeks of intervention with Huoxue Tongluo Qiwei Decoction and LY333531, serum level of sEselectin, LOX-1, sICAM-1, EMPs, CD62P and MDA in L, D and G groups were remarkably lower than group M while SOD level increased significantly, protein kinase C (PKC) pathway was inhibited with the improved erectile function of rats. Conclusion: Huoxue Tongluo Qiwei Decoction can inhibit the expression of protein and mRNA of the PKC beta signaling pathway related molecules in DIED rats to cure the injury of vascular endothelial, enhance antioxidant capacity, and prevent the activation of platelet, thus improving erectile function in rats with DIED.