Chlamydia pneumoniae is an obligate parasite capable of producing chronic infections. The severity of infection is closely related to hyperglycemia and changes in lipid profile. Since patients with Diabetes mellitus (DM) are at high risk of cardiovascular disease (CVD), the prevalence rate of specific C. pneumonia IgG / Ig A antibodies, its association to the change in diabetic control HbAc1 and lipid profile were estimated in 150 patients with DM and 50 healthy control subjects. C. pneumoniae (CPN) antibodies were estimated in 70% of DM patients using MIF and rDNA ELISA assays. 75 and 25% of patients were positive for CPN-IgG and IgA respectively using rDNA ELISA with prevelance rate 56.5 %, while 88 and 12% of patients were positive for CPN-IgG and IgA respectively using MIF assay which considered a gold standard method. There was significant (p=0.01) increase in the lipid profile except HDL-cholesterol (HDL-C) in diabetic patients with CPN-IgG antibodies compared to those having positive CPN-IgA antibodies.  Significant positive correlations in BMI, Total cholesterol, triglyceride, LDL-C and negatively with HDL-C were reported in diabetic patients with varying C. pneumoniae antibodies titers. The data obtained suggested that, the change in lipid profile and HbA1c may play a pivotal role in the severity of C. pneumoniae infection. Consequently, the reduction of lipid profile may be a new therapeutic target against C. pneumoniae infection in diabetic patients.