Background: The most common glomerular condition in children is idiopathic nephrotic syndrome (INS). Pneumococcal infections are one of the most serious consequences for children with nephrotic syndrome. Objective: Assessment of antibody titer in children with renal impairment 1- and 3-months after immunization with pneumococcal conjugate vaccine 13 (PCV13). Patients and Methods: Cross-sectional research including 24 nephrotic children was carried out at Pediatric Nephrology Unit and Outpatient Nephrology Clinics of Children Hospital at Zagazig University over a period of one year from April 2020 to March 2021. Results: At 1- and 3-months following vaccination, level of antibody titer was significantly higher among patients within group II. There was statistically significant difference between the studied groups regarding trend of antibody at three months. Steroid dosage at time of immunization was strongly associated with antibody titer one month (M) after vaccination in both groups. While there was statistically significant negative correlation between steroid dose at time and 3 months after vaccination with antibody titer at 3 months post vaccination in both groups. Conclusion: Nephrotic children in both groups can mount adequate antibody production to pneumococcal vaccine post vaccination, which is equal or higher than 0.35 μg/ml. On low doses of oral steroids and immunosuppressive medications, PCV-infected nephrotic youngsters developed strong protective antibody titers. Keywords: Nephrotic syndrome, Pneumococcal Vaccine, Post Vaccination.