Background: Diabetes mellitus is regarded to be one of the five leading induces of death in the world. Aim: The aim of this study is to estimate changes in the levels of biochemical parameters as fasting blood sugar (FBS), postprandial blood sugar (PP2BS) and glycosylated hemoglobin (HbA1c) together with immunological parameters as Complement proteins (C3 and C4), specific Immunoglobulin's (IgA, IgE, IgG, IgM) and C-peptide of type 1 diabetic patients to obtain a full immunological and physiological profile for type 1 diabetes. Subjects and Methods: Blood samples from 25 type 1 diabetic patients and 5 healthy control subjects were randomly selected from Zagazig University hospitals in Sharqiyya, Egypt. Serum blood sugar and glycosylated hemoglobin were measured following standard protocols and by using a chemical analyzer. C3, C4, IgA, IgE, IgG, IgM, and C-peptide were assayed by ELISA. Results: FBS, PP2BS and HbA1c significantly increased in type 1 diabetic patients compared to healthy control subjects. C4 and C-peptide significantly decreased in type 1 diabetic patients compared to healthy control subjects. IgG and IgM showed a significant increase in type 1 diabetic patients compared to healthy control subjects. Conclusion: Type 1 diabetes in the current studied subjects could be described as characterized by classically active complement system (abnormal C4 levels) which is induced by increased levels of IgG and IgM together with increased blood sugar levels (FBS, PP2BS and HbA1c) and decreased levels of C-peptide in serum.