Objective To investigate the phenomenon of excessive lumbar drainage after craniotomy, related preventive measures, and the safe volume of cerebrospinal fluid drainage in patients with spontaneous intracerebral hemorrhage.Methods The clinical data of 117 patients with spontaneous intracerebral hemorrhage who underwent craniotomy and lumbar drainage were analyzed retrospectively. The results showed that 101 patients among them did not experience excessive lumbar drainage (group B), and 16 patients experienced excessive drainage (group A). The average volume of cerebrospinal fluid drainage was compared between the two groups on days 1, 2, 3, 4, 5, 6, and 7.Results Among the 16 patients experiencing excessive drainage, the numbers of patients experiencing excessive drainage on days 1-7 were 1, 1, 6, 3, 3, 1, and 1, respectively. There were no significant differences in the volume of cerebrospinal fluid drainage on days 1, 2, 6, and 7 between the two groups (P>0.05), while there were significant differences in the volume of cerebrospinal fluid drainage on days 3, 4, and 5 (P<0.05). The two groups had a significant difference in the average volume of cerebrospinal fluid drainage through days 1-7 (P<0.05). The unilateral upper limit of 99% medical reference range for the patients without excessive drainage was 196.33 ml.Objective The patients may experience excessive drainage and related clinical symptoms during the 1-week lumbar drainage procedure, which mainly occurs on days 3-5. The daily volume of cerebrospinal fluid drainage should not exceed 196.33 ml, and this limit can significantly reduce the incidence of symptoms related to excessive lumbar drainage.