Objective To evaluate the early efficacy of hemiarthroplasty with different approaches in the treatment of dementia-induced femoral neck fracture using the concept of rapid rehabilitation. Methods A randomized, single-blind study was conducted to select 80 elderly patients with dementia femoral neck fracture who met the criteria from July 2018 to May 2020, and they were divided into two groups: group DAA (n=40) was used for hemiarthroplasty by direct anterior approach; group PLA (n=40) was used for hemiarthroplasty by posterolateral approach. Results 74 cases of 80 patients were followed up, the follow-up rate was 92.5%, the average follow-up time was 12.3 months (3-24 months). The incidence of complications in the two groups were 7.89% and 38.89% respectively, and the incidence of dislocation was 0% and 13.8% respectively. There were significant differences in incision length, blood loss, time of getting out of bed, hospital stay, Vas score two weeks after operation, Harris score two weeks after operation and complication rate between the two groups (p < 0.05) . Conclusion: Using the concept of rapid rehabilitation and DAA approach to treat senile dementia femoral neck fracture, the clinical effect is more significant in the early stage, such as minimally invasive treatment, less bleeding, less pain, short hospital stay, fewer complications, no postural restriction and low dislocation rate, it’s better for a quick recovery.