Abstract: In this paper, the development of the white blood cell in Chinemys reevesii was studied through the observation on the stained smears of the bone marrow, the spleen and liver etc. The results show that the bone marrow and spleen are the principal organs producing white blood cells in Chinemys reevesii, and that the development of the white blood cell consists of three stages, the primitive stage, the immature stage and mature stage. Morphological characters of the white blood cells at different stages were described. A preliminary discussion was made on the nomenclature and developmental patterns of white blood cells in Chinemys reevesii.