Objective To investigate the impact of staggered admission based on work system on waiting time and peak patient flow for day surgery patients. Methods A non-synchronous controlled intervention design was employed. Patients admitted to Day Surgery Center, West China Hospital, Sichuan University between June 11 and June 24, 2024, were designated as the control group, while patients admitted between July 8 and July 21, 2024, constituted the intervention group. The control group followed a centralized admission protocol with an admission window from 08:00 to 09:00, with patients notified of their arrival times by appointment nurses via phone. In contrast, the intervention group implemented a staggered admission schedule based on surgical scheduling, designating arrival times for first surgery, flexible, centralized, and turnover patients, supplemented by phone and text message reminders. The differences in waiting time and patient flow across time segments between the two groups were analyzed using the rank-sum test and chi-square test. Results Finally, 206 patients in the intervention group and 210 patients in the control group were enrolled in the study. The intervention group demonstrated significantly shorter admission waiting time for all admitted patients [22.0 (9.0, 44.0) vs. 35.0 (17.0, 55.0) min], admitted patients with normal conditions [15.0 (8.5, 34.5) vs. 31.0 (16.5, 48.0) min], and admitted patients with abnormal conditions [82.5 (51.0, 99.0) vs. 101.0 (76.0, 133.0) min], with statistically significant differences (P<0.05). During the peak hours from 08:00 to 10:00, the median patient flow in the intervention group was significantly lower than that in the control group (P<0.001). Specifically, during the peak period from 08:31 to 09:00, the median patient flow decreased from 34 (29, 36) to 25 (21, 27) , revealing a statistically significant difference (P<0.001). Conclusions Staggered admission can effectively reduce waiting times for day surgery patients across various admission scenarios and alter the distribution of patient flow during peak periods. Furthermore, the application of work system theory provides a theoretical basis for analyzing the complexity and uncertainty of day surgery admission management.