Ｏｂｊｅｃｔｉｖｅ　To evaluate the effects of intravenous administration of magnesium sulfate on the early recovery of female patients after thyroid surgery. 　Methods　Eighty female patients, aging 20-65 y, with body mass index (BMI) 18-30 kg/m2, American Society of Anesthesiologists(ASA) grades Ⅰ or Ⅱ, scheduled for thyroid surgery, were enrolled in this study. They were randomly divided into two groups (n=40): a magnesium sulfate group (group M) or a control group (group C). All patients received general anesthesia. Immediately after intubation, magnesium sulfate was intravenously administered at 50 mg/kg for 15 min, followed by 15 mg·kg-1·h-1 to the end of surgery. Group C received an equivalent volume of normal saline. The quality of recovery was assessed using the 40-item Quality of Recovery Questionnaire (QoR-40) scale one day before surgery (T1), and one day after surgery (T2) and two days after surgery (T3). The remifentanil consumption, response time, extubation time, the Visual Analogue Scale (VAS) score when entry into post-anesthesia care unit (PACU), the use of rescue analgesia, the incidence of nausea and vomiting, and PACU stay were recorded.　Results　Compared with group C, the remifentanil consumption[(0.065±0.018) μg·kg-1·min-1 vs(0.085±0.022) μg·kg-1·min-1] and VAS score at the time of arrival to PACU [1 (1, 2) vs 2 (1, 4)] were decreased, the physical comfort, emotional state, pain scores and global QoR-40 score in T2, T3 were increased in group M (P＜0.05). There was no statistical difference between two groups in the response time, extubation time, incidence of rescue analgesia, incidence of postoperative nausea and vomiting and time of PACU stay (P＞0.05).　Conclusions　Intravenously administered magnesium sulfate can improve the female patients′ quality of recovery during early period after thyroid surgery.