Aim: The aim of the present study was to determine the prognostic outcome of necrotizing fasciitis patientswith and without diabetes mellitus. Material and methods: The cross sectional comparative study was conducted in the department of General Surgery, Anugrah Narayan Magadh Medical College and Hospital , Gaya, Bihar, India for 2 years.100 cases of necrotizing fasciitis were equally divided into two groups, Group A for necrotizing fasciitis patients with diabetes mellitus and Group B for necrotizing fasciitis patients without diabetes mellitus. Hemoglobin, total leucocyte count, differential count, ESR, FBS, HbA1cand corresponding urine sugar on regular basis were investigated foe all the patients. Wound discharge for culture and sensitivity. were also done all the patients. Results: The mean ageis higher (57.1±14.33) in group A than group B (52.23±14.85). Out of 50 patients in group A, 10 (20%) were female, 40 (80%) were males. Out of 50 patients in group B, 8 (16%) were female, 42 (84%) were males. Out of 50 patients in group A, upper extremity was involved in 2 patients (4%), lower extremities were involved in 43 (86%) patients. Scrotum was involved in 3 (6%) patients, back was involved in2 (4%) patient. Out of 50 patients in group B, upper extremity was involved in 4(8%) patient, lower extremities were involved in 45 (90%), scrotum was involved in one (2%) patient. Out of 50 patients in group A, electrocution was the etiological factor in 1 (2%) patient, insect bite was the etiological factor in 3 (6%) patients, intramuscularinjection was the etiological factor in 2 (4%) patient, trauma was the etiological factor in 25 (50%) patients andno etiological factor was found in 19 (38%) patients. Outof 50 patients in group B, insect bite was etiologicalagent in 1 (2%) patient, thorn prick was etiologicalagent in 1 (2%), trauma was etiological agent in 23 (46%) patients, no etiological agent was identified in 25 (50%) patients. Out of 50 patients in group A, 45(90%) undergone split skin grafting surgery, 3(6%) undergone flap cover surgery and primary closure was done in 2 (4%) patient. Conclusion: Early diagnosis and aggressive debridement in necrotizing fasciitis patients results in better outcomes.