Introduction: Diphtheria, a potentially fatal upper airway infection, caused by Corynebacterium diphtheriae, still continues to be significant cause of morbidity and mortality in India, despite extensive immunization. Aims and objectives: This article aims to generate information about the clinical profile of patient of diphtheria in present times, assess association between immunization and severity of the disease and evaluate predictors that affect final outcome of the disease. Materials and methods: This is a retrospective study from June 2017 to June 2020 at a tertiary care teaching hospital. The relevant data of 33 cases who were either suspected or confirmed cases of diphtheria, were analyzed with respect to demographic details, clinical features, immunization status, treatment provided, complications, and final outcome. Results: Out of 33 cases, 72.7% were of age more than 5 years. Eighteen (55%) were nonimmunized, 10 (30%) were partially immunized, and 5 (15%) were immunized. The clinical features included fever, throat pain in all cases, membrane over tonsil in 93.7%, and bull neck in 78.1% cases. Albert stain was positive in 20 (60.6%) cases. Antidiphtheric serum (ADS) was given in 28 out of which 18 cases (64.3%) survived. Five cases did not receive ADS and out of these two (40%) survived. Case fatality rate was 55% in nonimmunized, 30% in partially immunized, and nil in immunized group. Overall, case fatality rate was 42.4%, and survival rate was 57.6%. Conclusion: As disease nowadays is affecting older children more, awareness about booster doses is required. Complete immunization, early ADS therapy irrespective of result of Albert stain, helps to decrease complications and improve survival.