Ｏｂｊｅｃｔｉｖｅ　To investigate the effects of dexmedetomidine (Dex) combined with dezocine in patient-controlled intravenous analgesia (PCIA) on the sleep quality, pain scores and adverse reactions in patients undergoing laparoscopic assisted vaginal hysterectomy.　Methods　Sixty patients who underwent laparoscopic assisted vaginal hysterectomy were randomly divided into two groups(n=30): a dezocine group(group C) and a Dex+dezocine group(group D). The primary observation indicators were the distribution of different periods of sleep[rapid eye movement(REM) sleep and non REM(M1, M2, M3) sleep], arousal index, sleep efficiency and subjective sleep quality score. The secondary indicators included visual analogue scale(VAS) scores, Ramsay sedation scores, mean arterial pressures (MAP), heart rate, pulse oxygen saturation(SpO2), nausea, and vomiting.　Results　Both groups presented remarkable decreases in M3 and REM stage sleep, sleep efficiency index and subjective sleep quality(P<0.05). Patients in group D showed greatly improved sleep effeciency index and subjective sleep quality, and marked reduced arousal index, compared with those in group C (P<0.05). Group D also indicated significantly higher ramsay sedation score than group C(P<0.05). There was a lower VAS score, a less incidence of nausea and vomiting, and more stable hemodynamics in group D.　Conclusions　The combined use of Dex and dezocine can improve sleep quality in patients after laparoscopic assisted vaginal hysterectomy, with less adverse reactions.