Bone marrow aspiration, referred to as bone aspiration, is one of the most common tests chosen by hematologists. Bone aspiration is performed to understand the proliferation of bone marrow and the presence of abnormal cell infiltration when patients present with multilineage blood cell abnormalities or anemia, reduced or increased white blood cells and platelets that cannot be explained by general causes. Due to the traditional concept, some patients become fearful when they hear about bone aspiration examination, worrying that it will affect their health. In fact, this fear is unnecessary. Bone marrow aspiration is just like a blood test, only a small amount of bone marrow fluid needs to be taken to meet the needs of the test, and the lost bone marrow fluid will soon be replenished by the blood-forming cells in the body, which will not have any adverse effects on the body. Bone marrow aspiration is also necessary for the diagnosis of malignant blood tumors such as leukemia and multiple myeloma. A portion of the bone marrow fluid is also usually retained for chromosomal and genetic testing, which can help with diagnosis and prognostic risk factor analysis. A repeat bone aspiration after treatment can assess the effectiveness of treatment. Having some understanding of the bone puncture procedure can help patients eliminate unnecessary worries and actively cooperate with the examination. Commonly used puncture sites are the anterior superior iliac spine, posterior superior iliac spine and sternum. The anterior superior iliac spine and the posterior superior iliac spine are the parts of the pelvis that protrude outward from the edges of both sides, and they are often chosen as puncture sites because they are closer to the skin surface, the bone surface is wider and flatter, and they are rich in marrow. The sternum also has the characteristics of being wide, flat and close to the body surface, but because both sides and the posterior side of it are critical parts of the mediastinum and the lungs and heart in the thoracic cavity, sternal puncture is less often chosen, and care needs to be taken to prevent injury during operation. Local anesthesia is used before the bone puncture, and a dermal mound is injected with anesthetic first, then the injection needle is inserted subcutaneously up to the periosteum, and the anesthetic is injected on the periosteum. Good or bad periosteal anesthesia is the key to whether the puncture is painful or not. After the needle has entered the bone marrow cavity, a syringe is attached to aspirate the bone marrow. The patient may experience momentary soreness while the bone marrow is being aspirated. After completing the bone marrow smear, the bone puncture site is then covered with clean gauze and fixed with adhesive tape, and normal activities can be performed after a short rest. Take care that the puncture site is not soaked with water for 3 days. Some patients may still feel localized soreness for two or three days after the bone puncture, which is normal and need not be overly worried, and the symptoms will soon improve.