Background: Diabetes mellitus type 2 (DMT2) is one of the most prevalent endocrine illnesses, affecting about 135 million individuals globally. The disease's genesis is unknown, but subclinical hemochromatosis has recently been identified as one of the possible causes of DM. The purpose of this study was to look at the association between serum ferritin as a measure of iron excess and diabetes and HbA1c. Methods: This 12-month study was carried out in the Medicine department of Katihar Medical College Hospital in Bihar, India. 46 patients with T2DM were used as cases in this case control study. The control group consisted of 46 healthy individuals who were age, gender, BMI, and haemoglobin percent matched to the case group. Blood samples were tested for ferritin, haemoglobin, HbA1c, and fasting plasma sugar. Anaemia and any other ailment or medicine that could alter ferritin levels were exclusion criteria. Result: The Pearson correlation coefficient test, Student's t-test, Chi-square test, and Odds ratio were used to assess the results statistically. Diabetics had considerably higher mean serum ferritin levels than the control group (197.97± 75.99 gm/L vs. 64.24± 27.83 gm/L, p<0.001). In diabetic patients, there was a substantial positive connection between HbA1c and serum ferritin (p<0.001). In this investigation, an OR of 11.64 was also discovered.