The operation process of bone marrow aspiration is to select the puncture site, take the position, disinfection, bone marrow aspiration fixator, remove the puncture needle and syringe, etc. 1. Selection of the puncture site: 1~2cm above the anterior superior iliac spine is the most commonly used site for bone marrow puncture because the bone surface there is flat and easy to be fixed, which makes the operation more convenient and safe. Besides, it can also be performed at the posterior superior iliac spine, sternal handle and lumbar spinous process, but it is less frequently used. 2. Positioning: assist the patient to take a suitable position. If the puncture is performed on the sternal pedicle or anterior superior iliac spine, the patient can be assisted to take a supine position, and the sternal pedicle puncture usually requires a pillow behind the back to make the chest slightly protrude. If the posterior superior iliac spine is punctured, the patient should be assisted to take the lateral position. For lumbar spinous process puncture, the patient can take the sitting position or side-lying position. 3. Disinfection: Routine disinfection of the skin at the puncture site, the doctor should wear sterile gloves and sterile towel, and then perform local anesthesia. 4. Puncture needle fixator: fix it at the appropriate length, withdraw the inner bolus for 1cm, pull out the needle core, and connect the sterile dry syringe, slowly aspirate with appropriate strength, usually a small amount of red bone marrow fluid can be seen into the syringe, and 0.1~0.2ml can be aspirated. 5. Remove the syringe and the puncture needle: when removing the puncture needle, at the same time, press the puncture site to stop bleeding, and then put the bone marrow fluid on the slide and make a smear for examination. The above is the operation procedure of bone marrow aspiration. It is recommended that patients go to professional hospitals for consultation, choose the appropriate puncture site with the help of doctors, and actively cooperate with doctors for bone marrow aspiration.