Dementia is a common mental disorder that affects the life quality in elders. Recently, emerging studies reported the negative impacts of dementia on prognosis after hip surgeries. However, the integrated and reliable role of dementia in hip surgery is not illustrated./r/nWe searched the relevant literatures before June 2020 and extracted the data that met the inclusion criteria. The influence of dementia on postoperative walking ability, complications including infection, cardiovascular complications, hip dislocation, delirium, and respiratory complications, and survival rate at different periods were evaluated. Qualitative and quantitative analysis were conducted using Review Manager Version 5.3./r/nThe meta-analysis enrolled a total of 30 studies with 1,037,049 patients. The pooled results revealed that there were significant negative impacts of dementia on the recovery of postoperative walking ability, postoperative infection, hip dislocation, delirium and respiratory complications and mortality at different periods./r/nDementia is a crucial risk factor for the poor prognosis after hip fracture surgery. Therefore, when making clinical strategies for hip fracture patients with dementia, countermeasures for possible complications should be generated.