Body Mass Index (BMI) is the index used to classify and score overweight and obesity. An imbalance between energy intake and expenditure may cause the accumulation of fat in the body, which affects the BMI value. BMI is used to detect metabolic syndrome, which is a collection of symptoms that can increase the risk of non-communicable diseases such as type 2 diabetes mellitus (T2DM) and cardiovascular disease. This study aims to determine the correlations between BMI and the incidence of metabolic syndrome at the internal medicine clinic Anutapura Hospital, Palu. This research was an analytic observational study with a cross-sectional approach. The samples were 96 patients and ATP III criteria was used in the assessment of metabolic syndrome. Individuals were declared metabolic syndrome if they met 3 out of 5 criteria, namely increased waist circumference, blood pressure, fasting plasma glucose (FPG), triglyceride levels, and decreased HDL levels. Data analysis used a chi-square test. It obtained a p-value = 0.001 with the results that showed a correlation between BMI and the incidence of metabolic syndrome at the internal medicine clinic, Anutapura General Hospital, Palu. There were correlations between BMI and waist circumference (p = 0.000), blood pressure (p = 0.003), triglycerides (p = 0.000), and HDL (p = 0.000). There were no correlations between BMI and FPG levels (p = 0.531). There is a correlation between BMI and the incidence of metabolic syndrome in the internal medicine clinic Anutapura Hospital, Palu.