The prevalence of diabetes mellitus has increased over time. Patient compliance in taking medication and medical nutrition therapy plays a very important role in the success of treatment to maintain blood glucose levels within the normal range. The purpose of this study was to determine the effect of family support, health workers and food availability on compliance with medical nutrition therapy in patients with type 2 diabetes mellitus. This study is an analytical observational study with a cross-sectional approach. This study was conducted from April to October 2023. The research sample was 95 diabetes mellitus patients in the work area of ​​the Kalirejo Public Health Center in Pesawaran Lampung. The sample was taken using a purposive sampling technique that met the inclusion and exclusion criteria. Data on family support, health workers and food availability were taken using a validated questionnaire, and data on compliance with medical nutrition therapy were assessed by comparing food intake with the nutritional needs of patients based on the 2x24h food recall questionnaire. Data were analyzed using chi square and logistic regression. The results showed that non-compliance with medical nutrition therapy in patients with type 2 diabetes mellitus was 80%. Family support, health workers and food availability are related to compliance with medical nutrition therapy in diabetes mellitus patients (p=<0.001; p=0.004; p=0.02). Compliance with medical nutrition therapy in type 2 diabetes mellitus patients is very necessary in controlling blood sugar in order to prevent complications. Family support and health workers play an important role in compliance with medical nutrition therapy in type 2 diabetes mellitus patients.