Background: Diabetic ulcer is a complication in patients with diabetes mellitus characterized by chronic wounds on the foot that are difficult to heal, due to nerve damage and impaired blood flow. Drug resistance, especially to antibiotics occurs due to improper use and increases the risk of amputation to be a significant problem in treatment of diabetic ulcer. Objective: This study aims to evaluate the use of antibiotics in outpatients with diabetic ulcer at Ulin Banjarmasin Hospital in 2023. Methods: This research method is descriptive observational quantitatively and qualitatively, taken retrospectively from medical record data, the population and sample are outpatients with diabetic ulcer at Ulin Hospital, totaling 100 samples. Results: Based on the result of the study on 100 samples evaluations of the ATC/DDD method with a total antibiotic use of 978,66 DDD/patients days, the highest antibiotic was Cefixim (41,429%)and the lowest antibiotic was Metrodinazole (20,417%). Antibiotic included in the 90% segments are Cotrimoxazole (36,13%), Cefixim (34,75%), and Ciprofloxacin (11,18%), while the 10% segments is Clindamycin (9,54%) and Metrodinazole (8,41%. Evaluation of the Gyssens method obtained category 0 as many as 40 patients, category I as many as 33 patients, and category IVA as many as 27 patients. The result of the chi square of the Fisher’s Exact Test analysis of the Gyssens category with sig. value of 0.000<0.05 and the use of antibiotic Cefixim, Clindamycin, Ciprofloxacin, Cotrimoxazole, and Metrodinazole with a sig. value of 0.000<0.05. Conclusion: Based on the results of quantitave and qualitative evalution of antibiotic use, it was concluded that the quantity of antibiotic use exceeding WHO standars has potential to cause resistance, and the quality of antibiotic use in outpatient diabetic ulcer at Ulin Hospital in 2023.