Leukemia complicated by central nervous system (CNS) lesions (LCNSL) includes leukemia involving the CNS (CNSL) and CNS secondary lesions related to leukemia treatment (e.g., CNS infections, leukoencephalopathy, inflammatory demyelination, and vascular diseases). The clinical manifestations and imaging characteristics of different types of LCL are similar, increasing the possibility of misdiagnosis. This study aimed to enhance our understanding and management of LCL.We retrospectively collected clinical data from 22 patients with LCL and analyzed their magnetic resonance imaging and pathological characteristics. Pathological diagnoses were made using stereotactic intracranial puncture biopsy.Between April 2003 and December 2023, 22 patients with LCL were admitted, including 18 males and 4 females aged 7-71 years. Bone marrow aspiration identified 14 cases of acute lymphoblastic leukemia (ALL), one of chronic lymphoblastic leukemia, six of acute myeloid leukemia (AML), and one of chronic myelomonocytic leukemia (CMML). Most patients presented with non-specific symptoms, including headache, nausea, vomiting, limb convulsions, and changes in mental status. A few patients had localized neurological deficits, such as limb weakness and blurred vision. Common systemic symptoms included fever, night sweats, and weight loss. The pathological diagnoses of the 22 patients were CNSL in 13 patients, CNS infections in five patients, and neurodegenerative diseases in four patients. Discrepancies were found between the clinical and pathological diagnoses in eight cases.Stereotactic intracranial lesion biopsy is minimally invasive, safe, convenient, and critical in the early and differential diagnosis of LCL. Early identification of the lesions' nature and timely implementation of accurate and precise treatments can improve patient prognosis.© 2025. The Author(s).