Objective To analyze the factors influencing day surgery developing towards same-day surgery, and provide a reference for the promotion of same-day surgery. Methods A questionnaire on influencing factors of same-day surgery was prepared based on structural equation modeling (SEM), including 6 dimensions and 23 items. From January to October 2021, at the Day Surgery Center of West China Hospital, Sichuan University, the random sampling method was used to select the research subjects for a questionnaire survey, and SEM was used to analyze the factors impacting the iterative development of day surgery to same-day surgery service model. Results A total of 200 questionnaires were distributed, and 192 valid questionnaires were recovered, with an effective recovery rate of 96.0%. The Cronbach’s α coefficient of the questionnaire was 0.857, and the Cronbach’s α coefficient of each dimension was from 0.832 to 0.934. The KMO test value was 0.822, and the result of Bartlett sphericity test was χ2=4568.330, P<0.001. The model fit indexes met the standard requirements well. The result of SEM revealed that the standard path coefficients of “the hospital’s preliminary preparation for day surgery developing towards same-day surgery” impacting “the guarantee system related to surgical quality and safety”, “the guarantee system related to surgical quality and safety” impacting “the public’s awareness of day surgery developing towards same-day surgery”, “the guarantee system related to surgical quality and safety” impacting “the ‘hospital-community’ integrated collaboration network”, “the public’s awareness of day surgery developing towards same-day surgery” impacting “the ‘hospital-community’ integrated collaboration network”, and “the ‘hospital-community’ integrated collaboration network” impacting “the iterative upgrade of day surgery” were all larger than 0.5, indicating strong influences between these factors, but the absolute value of standard path coefficient of the “hospital’s development brought by the transform of day surgery to same-day surgery” impacting “the guarantee system related to surgical quality and safety” was smaller than 0.3. Conclusion The hospital’s preliminary preparation, the guarantee system related to surgical quality and safety, the development of the “hospital-community” integrated collaboration network, and the public’s awareness are the probable factors influencing the iterative development of day surgery to same-day surgery.