Mainly related to the site of bleeding and the amount of bleeding mild cases can be asymptomatic, a large number of bleeding can die in a short period of time. Common symptoms and signs are: 1. mental changes: agitation, drowsiness or coma; 2. respiratory changes: increased or decreased, irregular or suspended; 3. increased intracranial pressure: bulging fontanelle, increased blood pressure, convulsions, corneal inversion, cerebral scream; 4. eye signs: gaze, strabismus, difficulty in turning up the eye, nystagmus, etc.; 5. loss of pupillary response to light; 6. muscle tone: increased, decreased or lost; 7. Others: unexplained pallor, anemia and jaundice. In addition, depending on the site of hemorrhage, it is clinically classified into the following types: 1. Periventricular-intraventricular hemorrhage is a common type of intracranial hemorrhage. It is mainly seen in premature infants with gestational age less than 32 weeks and weight less than 1500g. 2.Primary subarachnoid hemorrhage is very common in newborns, mostly without clinical symptoms, some of them may have convulsions, and very few cases die of massive hemorrhage. 3, brain parenchymal hemorrhage, depending on the site and amount of bleeding clinical symptoms vary greatly. In case of brainstem hemorrhage, pupillary changes, irregular breathing and bradycardia may occur. 4.Subdural hemorrhage. 5.Cerebellar hemorrhage.