Objective To study the effect of dexmedetomidine (Dexmedetomidine,Dex) on the quality of recovery after cesarean section and its related factors. Methods one hundred patients undergoing cesarean section under combined spinal-epidural anesthesia were randomly divided into two groups: Dex group (group D, n = 50) and control group (group C, n = 50). After the delivery of the severed umbilical cord, group D was given a load dose of Dex 0.5μg·kg-1 for 10 minutes, and then 0.5 μg·kg-1·h-1 was pumped to the end of the suture skin. Group C was given the same volume of normal saline, and postoperative analgesia was performed with PCIA (total volume 100ml): D group: Dex 2 μg·kg-1 + sufentanil 1.5 μg·kg-1,C group: 1.5 μg·kg-1 sufentanil group. The QoR-40 scores at 1st, 3rd, and 5th days, analgesic remedies within 48h and adverse reactions after operation were recorded. According to the scores of QoR-40 at 3rd day after operation, the patients were divided into two groups: high score (170, 76 cases) and low score (≤170, 18 cases). The maternal age, education years, operation time, intraoperative blood loss, visceral pain traction reaction of parturients before pumping (T1), after pumping 5min (T2), 10min (T3), cleaning exploratory abdominal cavity (T4), and at the end of operation (T5), the VAS pain score (quiet and tumbling) and Ramsay Sedation score at 2h, 4h, 6h, 12h and 24h after operation, FS-14 fatigue scores at 1st and 3rd days after operation, scores of hospital anxiety and depression scale(HADS), subjective sleep quality scores and husband's accompanying delivery were collected. Univariate and multivariate Logistic regression analysis was used to analyze the related factors. Results The QoR-40 scores of parturients in group D was significantly higher than that in group C at 3rd day after operation(P0.05). There were no significant differences in postoperative analgesia recovery remedy rate and adverse reaction rate between the two groups (P0.05). The results of univariate analysis showed that there were significant differences in preoperative anxiety score, preoperative fatigue score, anxiety, depression and fatigue score at 1st and 3rd days after operation, and VAS pain score at 4 h, 12 h (turning over) and 24 h (quiet) between the two groups in QoR-40 high score group and low group(P0.05). Multivariate Logistic regression analysis showed that preoperative anxiety scores was an independent risk factor for postoperative recovery. Conclusion Dexmedetomidine can improve the QoR-40 scores at 3rd day after cesarean section, without increasing the incidence of postoperative adverse reactions and promoting postoperative recovery, and there are many factors affecting the recovery of patients after cesarean section, among which preoperative anxiety score is the main factor affecting the recovery of patients after cesarean section.