This article focuses on a case study of sitosterolemia in a child who initially presented with hemolytic anemia and thrombocytopenia.Sitosterolemia is a rare autosomal recessive lipid metabolism disorder,difficult to diagnose due to its non-typical clinical manifestations.The 8-year-old patient was initially misdiagnosed with pyruvate kinase deficiency.Comprehensive biochemical and molecular biology analyses,including gene sequencing,eventually led to the correct diagnosis of sitosterolemia.This case highlights the complexity and diagnostic challenges of sitosterolemia,emphasizing the need for increased awareness and accurate diagnosis in patients presenting with similar symptoms.