This study compared the levels of CSF-Cl, CSF-GS, CSF-MALB, and CSF-ADA between the hemorrhagic hydrocephalus group (H-HCP group) and tumor hydrocephalus group (T-HCP group) from January 2018 to April 2022 to explore the value of these four indicators in the differential diagnosis of secondary hydrocephalus, so as to provide clinical data support for the diagnosis and treatment of secondary hydrocephalus [19, 20]. The gene discussed is ADA; the disease is Hydrocephalus.