Chronic subdural hematoma is more common in the elderly and should be treated surgically once symptoms of increased intracranial pressure appear. Traditional treatment methods: 1, drilling or cone hole flushing and drainage: according to the site and size of the hematoma, two holes (one high and one low) are chosen before and after, and the liquid hematoma is drained by silicone tube or No. 8 urinary catheter, which usually needs to be removed in 3 to 5 days. 2.Bone flap craniotomy for chronic subdural hematoma removal: it is suitable for chronic subdural hematoma with thicker envelope or with calcification, and bilateral hematoma should be operated in stages and by side. Whether drilled and drained or craniotomized, there is the problem of hematoma recurrence. Common causes of recurrence include: brain atrophy in elderly patients, difficulty in postoperative brain expansion; thick hematoma envelope, failure to close the subdural cavity; failure to completely remove blood clots from the hematoma cavity; and recurrence of hematoma due to fresh bleeding. Therefore, it is necessary to pay attention to the precaution that after surgery, it is advisable to adopt a low head position, lie on the affected side, drink more water, do not use strong dehydrating agents, and supplement hypotonic fluids appropriately if necessary; craniotomy should be performed to remove the thick envelope or calcification; when there is a solid clot in the hematoma cavity or fresh bleeding, a bone flap or window should be used to open the cranium and remove it completely. With the application of electronic soft neuroendoscope, the hematoma can be removed in one time under direct endoscopic view after a hole is drilled, and the bleeding point can be stopped by electrocoagulation without external drainage after surgery, which can effectively reduce the chance of recurrence of hematoma and bone flap craniotomy with less trauma and better results. Especially for those with repeated bleeding and multiple separations in the hematoma cavity (as shown in the figure), the hematoma separation can be opened under endoscopy for one-time cure.