Background– The burden of Diabetes Mellitus is increasing worldwide and it is estimated to reach indefinite proportions of about 450 million by year 2030. Objectives – To investigate the changing levels of tumor necrosis factor–alpha, insulin resistance, glycosylated hemoglobin , body mass index and blood lipid profiles in diabetic patients with obesity and to analyze the co–relation of Tumor necrosis factor with insulin resistance and blood lipid profiles. Material and Methods– It was a hospital based study conducted in the department of biochemistry at People’s College of Medical Science & Research Centre Bhopal (M.P.). Patients with complication of diabetes like diabetes neuropathy, nephropathy, retinopathy etc. were excluded. Epi–info software was used for statistical analysis. Results– There is a significant difference in tumor necrosis factor– alpha, insulin resistance, glycosylated hemoglobin , total cholesterol and high density lipoprotein. Tumor necrosis factor–alpha is significantly associated with insulin resistance with group 1. Conclusion– Tumor necrosis factor– alpha may be involved in the etiology of insulin resistance in type II diabetes mellitus with obesity.