Background: Diabetes will be the 7th leading cause of death by 2030 as per the World Health Organization (WHO). Encouraging the populace to use drugs rationally is the main goal of research on drug usage. Aims and Objectives: The objective of this study is to determine drug utilization pattern among patients with diabetes mellitus using the WHO Core Indicators in a tertiary care hospital, Indore. Materials and Methods: A prospective and observational study was done in the Department of Pharmacology along with the Department of Medicine in MGM Medical College and Hospital, Indore. After taking informed consent from diabetic patients visiting the outpatient department, their demographic details and prescriptions were recorded in case record form and analyzed using WHO core indicators. Results: In our study, total prescription assessed was 123. The total drugs prescribed were 652, out of which a total of 278 were anti-diabetic drugs. The average number of drugs per encounter = 5.3. Percentage of drugs prescribed by generic name = 92.4%. Percentage of encounters with an antibiotic prescribed = 10.5%. Percentage of encounters with an injection prescribed = 34.9%. The percentage of drugs prescribed from the essential drugs list (2015) = 72.3%. Conclusion: Prescribing pattern of antidiabetic drugs vary a little from the WHO standards. Rational prescription should be encouraged and such studies should be done regularly for periodic auditing of prescription.