Objective To investigate the value of ropivacaine combined with dexmedetomidine and dexamethasone of ultrasound-guided interscalene brachial plexus block (IBPB) in arthroscopic shoulder surgery.Methods Totally 102 patients who planned to undergo arthroscopic shoulder surgery by ultrasound-guided IBPB were selected and divided into 3 groups by random number table method. Group A (34 cases) was treated with 30 ml 0.375% ropivacaine，group B (34 cases) was treated with 30 ml 0.375% ropivacaine and 1.0 μg/kg dexmedetomidine, group C (34 cases) was treated with 30 ml 0.375% ropivacaine and 1.0 μg/kg dexmedetomidine and 10 mg/kg dexamethasone. Compared the effect of sensory block, motion block, pain visual analog scale (VAS) score and complications between 3 groups.Results The onset time of sensory block, completion time of sensory block, onset time of motor block, and duration of motor block in group C were shorter than those in group B and A (P < 0.05), and group B was shorter than that in group A (P < 0.05). The sensory block score of group C was lower than that of group B and A (P < 0.05), and group B was lower than that of group A (P < 0.05). Pain VAS scores at postoperative 3 h, 6 h in group C was higher than that in group B and A (P < 0.05), and group B was lower than that of group A (P < 0.05). The proportion of sufentanil in group C was lower than that in group B and A (P < 0.05), and group B was lower than that in group A (P < 0.05). The complication rate of group C was lower than that of group B and A (P < 0.05).Conclusion Ropivacaine combined with dexmedetomidine and dexamethasone of ultrasound-guided space brachial plexus nerve block can enhance the analgesic effect and have low adverse reactions.