A drainage device for 
intracranial hematoma cranium drilling is characterized by comprising a double-cavity 
catheter, a drainage tube, a dredging 
balloon, a drainage bag and a reverse flowing prevention tee joint. The double-cavity 
catheter is provided with a first tube cavity and a second tube cavity, wherein the first tube cavity and the second tube cavity are mutually isolated, the first tube cavity is used for drainage and connected with the drainage tube, and the second tube cavity is used for 
medicine injection and flushing and connected with an injection tube. The double-cavity 
catheter is arranged, so that drainage, flushing, and 
medicine injection are performed in different channels, it is guaranteed that the channels are kept sanitary and clean, and 
intracranial infection is prevented. The reverse flowing prevention tee joint is used for preventing hydrops from flowing reversely so that 
secondary infection and danger can be prevented. Scales are arranged on the drainage tube and the drainage bag, the dredging 
balloon is connected with an air pressure adjusting 
assembly, and the scales and the air pressure adjusting 
assembly are arranged, so that it is avoided that the operation force can not be mastered due to insufficient experience, and operation stability is improved. In addition, the drainage device is further provided with a dropping 
bottle and the dredging 
balloon, so that the channels are convenient to observe and prevented from being blocked.