Objective To investigate the efficacy and safety of paracervical block combined with alfentanil in hysteroscopic day surgery under total intravenous anesthesia. Methods This study used a prospective randomized controlled study approach. A total of 60 day surgery patients requiring hysteroscopic surgery under general anesthesia admitted to Weifang People’s Hospital between October and December 2020 were randomly selected. All patients were divided into trial group and control group by completely random number table method, with 30 patients in each group. The trial group received paracervical block combined with total intravenous anesthesia with alfentanil, and the control group received total intravenous anesthesia with alfentanil. The general condition, operation time, recovery time, intraoperative propofol dosage, postoperative pain score, intraoperative motion response and postoperative nausea and vomiting incidence were compared between the two groups. Results There was no significant difference in age, body mass index and incidence of comorbidities between the two groups (P>0.05). There was no significant difference in the operation time, recovery time, pain score at 2 hours after operation, and incidence of nausea and vomiting between the two groups (P>0.05). In the control group, the dose of propofol [(34.07±12.67) vs. (28.33±9.10) mL], the pain score on awakening (1.50±0.78 vs. 0.77±0.50), and the incidence of body movement response (20.0 % vs. 0.0%) were higher than the trial group (P<0.05). Conclusion The use of paracervical block combined with alfentanil in hysteroscopic day surgery under total intravenous anesthesia can reduce the amount of propofol during the operation, reduce postoperative pain, and reduce perioperative adverse reactions, which has a good efficacy and safety.