Diabetic ulcers are chronic wounds that are notoriously difficult to treat, leading to significant physical and psychological distress and increased healthcare costs. Their multifactorial aetiology necessitates long-term interdisciplinary collaboration and various complementary treatment measures. While numerous studies suggest that electrical stimulation (ES) positively impacts diabetic ulcer healing, the robustness and consistency of these findings require further evaluation to optimize clinical application. We searched databases including PubMed, the Cochrane Library, Embase, Web of Science and the China National Knowledge Infrastructure (CNKI). Only randomized clinical trials (RCTs) comparing ES treatment to placebo or conventional treatment were included. Extracted information included objective healing measures and data for assessing effect sizes. Ten RCTs involving 451 patients met inclusion criteria. ES improved ulcer healing rate compared to control or placebo (MD 20.37, 95% CI: 16.89–23.85, p <0.001) and increased the number of healed ulcers (RR 1.45, 95% CI: 1.18–1.78, p <0.001), with both results being statistically significant. The observed benefits are likely due to the positive effects of ES on the vascular and neurological functions of the lower limbs in patients with diabetic ulcers. Both low-frequency, moderate-intensity alternating current and low-intensity or high-voltage direct current have demonstrated efficacy in promoting ulcer healing. The results suggest ES may be a promising approach of managing diabetic ulcers. However, the optimal method of ES application remains undetermined; therefore, high-quality and large-scale studies are essential.