Abstract:The anatomical and histological characteristics of spleen, head kidney and trunk kidney of Hemibarbus labeo were studied by dissection, paraffin sections and H. E staining. The results showed that the spleen is single with dark red. It is applanate and oval, and is separated into many lobes by the connective tissue diaphragm from the capsule. The boundary between red pulp and white pulp in the lobes is not obvious. The spleen contains many of the red blood cells, lymphocytes and melano-macrophages, and the blood vessels are rich. The kidney can be obviously divided into the head kidney and the trunk kidney. The head kidney is located above the diaphragm of the back of the heart at the front end of the body cavity, divided into left and right lobes, and distributed symmetrically. The parenchyma of the head kidney has no nephron, and is mainly composed of lymphoid tissue, including red blood cell centers and white blood cell canters. The head kidney also contains many of red blood cells, lymphocytes, granulocytes, and a certain number of melano-macrophages, which are similar to the spleen. The trunk kidney is located in the thoracic and abdominal segments of the fish body, and close to the two sides of the spine on the back of the body cavity. Its parenchymal part is mainly composed of nephron, collecting segment and lymphoid tissue. Many of red blood cells, lymphocytes, granulocytes, and melano-macrophages can be observed in the lymphatic tissue. These results indicated that the spleen and head kidney are important immune and hematopoietic organs, and the trunk kidney also plays an important role in immunity and hematopoiesis in addition to urinary function in H. labeo.