Objective: To investigate the impact of ventriculoperitoneal shunting during clinical rehabilitation of chronic normal pressure hydrocephalus patients with disorders of consciousness following aneurysmal subarachnoid haemorrhage. Design: Cross-sectional study. Patients and methods: Thirty-five patients with disorders of consciousness following aneurysmal subarachnoid haemorrhage who had undergone ventriculoperitoneal shunting for chronic normal pressure hydrocephalus were compared with 16 matched controls with no ventriculoperitoneal shunting. Data from clinical examinations, rehabilitation assessments and computed tomography scans (to exclude other diseases that can cause ventricular enlargement) were analysed. All the patients with disorders of consciousness underwent neurorehabilitation. Consciousness was measured on the Glasgow Coma Scale. The cella media index was calculated as the change in size of the lateral ventricles (prior to ventriculoperitoneal shunting and/or rehabilitation, and 1 and 3 months after shunting and/or rehabilitation). The short-term outcome of treatment was assessed at 3 months using the Glasgow Outcome Scale. Results: Twenty-four out of 35 patients with disorders of consciousness recovered gradually after ventriculoperitoneal shunting and rehabilitation. There was a significant difference in the Glasgow Coma Scale between ventriculoperitoneal shunting and control groups at both 1 and 3 months (F=19.29, p<0.01). Significant differences were also observed between the 2 groups in the cella media index at 1 and 3 months (F=15.03, p<0.01). The Glasgow Outcome Scale of the ventriculoperitoneal shunting group was significantly higher than that of the control group (p<0.01, r=0.55) 3 months after shunting and/or rehabilitation. Conclusion: Chronic normal pressure hydrocephalus during rehabilitation is a serious and previously unrecognized medical condition, which influences consciousness in patients following an aneurysmal subarachnoid haemorrhage. However, the condition can be treated by ventriculoperitoneal shunting, which helps some patients with disorders of consciousness to regain consciousness.