Introduction Chronic leg ulcers impact patients' quality of life and pose a therapeutic challenge for dermatologists. The aim of this study was to evaluate the efficacy of LED monotherapy on healing and pain in the treatment of chronic leg ulcers. Materials and Methods his prospective descriptive study was conducted at the Laser Unit of the Dermatology and Venereology Department at Ibn Rochd University Hospital in Casablanca from July 2021 to May 2023. Inclusion criteria were the presence of a leg ulcer and age > 18 years. Exclusion criteria included uncontrolled diabetes and pregnancy. We used a polychromatic LED device combining five colors: violet (415nm), blue (465nm), yellow (590nm), red (630nm), and infrared (850nm), in continuous mode with total fluences of 48J/cm2 and 64J/cm2. Results 23 patients were recruited, with 78.3% being male and a male-to-female ratio of 3.6. The average age was 44.5 years (19-70 years). Vascular etiology was found in 65.2% of cases. Enzyme deficiency was observed in 17.4%: prolidase deficiency and protein C deficiency. Leg ulceration related to a systemic disease was noted in 17.4%. Hematological etiology was identified in 8.7%: sickle cell disease and thalassemia. At the end of treatment, pain regression was noted in 72% of cases. Healing was complete in 26.1% of cases and partial in 73.9%. Conclusion Chronic ulcers represent debilitating conditions with challenging healing. LED therapy using a combination of colors (violet, blue, yellow, red, infrared) accelerated the healing of chronic leg ulcers of various etiologies and reduced pain. Further largescale comparative studies are needed to assess the effectiveness of LED therapy with color combinations in the healing of chronic leg ulcers and to establish practical usage recommendations.