Hematopathology is the practice of pathology concerned with the study and diagnosis of human diseases involving the hematopoietic tissues.

Hematopathologists study of diseases and disorders affecting blood cells, their production, and any organs and tissues involved in hematopoiesis, such as bone marrow, the spleen, and the thymus. Diagnoses and treatment of diseases such as leukemia and lymphoma often deal with hematopathology; techniques and technologies include flow cytometry studies and immunohistochemistry.