The adjuvant effectiveness of nalbuphine in context of brachial plexus block (BPB) in patients undergoing upper-limb orthopaedic trauma surgery has remained uncertain. The purpose of this meta-analysis was to evaluate the analgesic benefit of mixing nalbuphine into local anaesthetics in BPB for wound pain from upper-limb trauma surgery. Primary outcome was the duration of analgesia. Seventeen trials (1104 patients) were analysed. Patients receiving nalbuphine have an increased weighted mean difference (WMD) 95% confidence interval of the duration of analgesia by 186.91 minutes (133.67 to 240.16) (P < 0.001). Compared to placebo, nalbuphine shorten the onset time of sensory and motor block by WMD of 2.59 (1.27 to 3.92) and 3.06 minutes (1.65 to 4.48) (P < 0.001), respectively. Meanwhile, nalbuphine prolonged the durations of sensory and motor block (P < 0.001). Qualitative and quantitative synthesis revealed no differences with regard to the outcomes related to side-effects. There is moderate-quality evidence that the addition of nalbuphine to local anaesthetics for BPB in patients undergoing upper-limb orthopaedic trauma surgery significantly prolongs the duration of analgesia, while preserving a similar safety-profile compared with local anaesthetics alone. However, these benefits should be further weighed against nalbuphine-related neurological safety in future studies.