The purpose of this study was to describe rituximab biosimilar safety in adult hematology and pediatric nephrology units. Adverse events were classified using the Common Terminology Criteria for Adverse Events (CTCAE) classification. Fifty adult patients were enrolled for a total of 126 cures and 11 pediatric patients for a total of 24 biosimilar cures. Among adults, three infusion-related reactions of biosimilar occurred : a bronchospasm, a reaction at the injection site and emesis. Among children, infusion-related reactions were: a bronchospasm, an injection site reaction, an emesis, and diarrhea. For adults, the most common adverse events included neutropenia (13.5 %) with 9 severe grade 3/4 cases, anemia (8.7 %), grade 1 thrombocytopenia (6.3 %), asthenia (2.4 %), infection (2.4 %), and chills (1.6 %). For children, a case of severe grade 4 neutropenia, a fever and conjunctivitis were observed. Results of this study show a confident safety profile of rituximab biosimilar in adults and children in «real life».