Objective: to identify the prevalence of type 2 diabetes mellitus in geriatric patients and evaluate the impact of the risk factors (modifiable and non-modifiable) of this pathology. Methods: the study was retrospective case design and controls unpaired through medical records and had 250 geriatric patients from a public hospital in North Lima grouped in cases (150 older adults with type 2 diabetes mellitus) and controls (100 older adults without type 2 diabetes mellitus) during the year 2018. A univariate, bivariate and multiple analysis was used with the Stata version 14 program. Results: the prevalence of type 2 diabetes mellitus was 50%. In addition, the modifiable factors associated with diabetes mellitus were increased triglycerides (adjusted OR: 1.06 95% CI: 1.03-1.09) and overweight (adjusted OR: 2.93; 95% CI: 0.98-8.70). Conclusion: the percentage of type 2 diabetes mellitus in geriatric patients is 60%. Likewise, high triglyceride and overweight values are the modifiable impact factors to the presence of type 2 diabetes mellitus.