The autoimmune mechanism in T1DM causes gradual loss of pancreatic β-cell, which progresses to hyperglycemia and ultimate reliance on consistent insulin therapy. T1DM has been the commonest type of diabetes in children and this study will help in refining indulgent towards the problem and its pathophysiology in our people. The objective was to find out the prevalence of C-peptide and antibody levels (anti GAD, ICA, IAA and IA2) in children and adolescents of Pakistan with T1DM. We conducted this cross-sectional study at Department of Pediatric Endocrinology, National Institute of Child Health, Karachi between August 2019 to February 2020 and included 98 children who had T1DM for more than one month. Subjects whose GFR was <30ml/min were omitted from the study. Among those registered subjects, C-peptide, human islet cell antibody (ICA), insulin auto antibodies (IAA) and anti-glutamic acid decarboxylase were assessed. Demographical and laboratorial facts were noted on a pre-constructed proforma. There were 77(78.3%) cases who had level of C-peptide <0.8 and anti-GAD was found in 47(48%) subjects. 35(35.7%) cases found positive for IA2 .and 7(7.1%) patients had insulin auto antibodies positive while ICA was negative in total 98(100%) subjects. Children with T1 DM possessed increased levels of anti-GAD antibodies, insulin autoantibodies and anti (IA2) but islet cells antibodies were negligible in our population when checked at a point of time. C-peptide may be normal in some, but its level declines with long duration of diabetes in children.