The early recovery of hip function after hip fracture surgery values more attention, especially for patients with delayed surgery of longer than 48 hours. We aim to evaluate the associations of in-hospital surgical waiting time with the functional outcomes (Harris Hip score, Parker Mobility Score and EuroQol 5 dimensions VAS score) in elderly patients who sustained hip fractures.Data on sociodemographic and clinical factors were prospectively collected using a multicenter hip fracture registry system. Participants in the cohort underwent a 12-months follow-up investigation. After adjusting potential confounders identified by the directed acyclic graphs, the associations between surgical waiting time longer than 48 hours and functional outcomes were estimated by log-binomial regression and multivariable linear regression models with generalized estimating equations.Of 863 survival participants with available functional data at 12 months after surgery, an increased risk was obtained from receiving surgery after 48 hours and the poor functional outcomes (HHS<80: RR=1.56, 95%CI 1.00, 2.51; PMS<7: RR=1.49, 95%CI 1.13, 2.01; EQ-5D VAS<80: RR=1.97, 95%CI 1.57, 2.47). In-hospital waiting time>48 hours were time-invariantly associated with lower PMS during recovery (-0.44 units 95%CI -0.70, -0.18). In addition, delayed surgery was time-varying associated with HHS and EQ-5D VAS.The associations between in-hospital waiting time and postoperative functional score suggest that delayed surgery can lead to poor functional outcomes, especially in patients waiting longer than 72 hours from injury. Delayed surgery mainly impacting hip function and mobility recovery with a slower speed in early recovery of the first three months. More attentions should be paid to mechanisms behind the associations between delayed surgery on general healthy status.Copyright © 2023 the Author(s). Published by Wolters Kluwer Health, Inc.