Background Music is a non-invasive, safe, and inexpensive intervention that can be delivered easily and successfully. We did a systematic review and meta-analysis to assess whether music improves recovery after surgical procedures. Methods We included randomised controlled trials (RCTs) of adult patients undergoing surgical procedures, excluding those involving the central nervous system or head and neck, published in any language. We included RCTs in which any form of music initiated before, during, or after surgery was compared with standard care or other non-drug interventions. We searched MEDLINE, Embase, CINAHL, and Cochrane Central. We did meta-analysis with RevMan (version 5.2), with standardised mean diff erences (SMD) and random-eff ects models, and used Stata (version 12) for meta-regression. This study is registered with PROSPERO, number CRD42013005220. Findings We identifi ed 4261 titles and abstracts, and included 73 RCTs in the systematic review, with size varying between 20 and 458 participants. Choice of music, timing, and duration varied. Comparators included routine care, headphones with no music, white noise, and undisturbed bed rest. Music reduced postoperative pain (SMD –0·77 [95% CI –0·99 to –0·56]), anxiety (–0·68 [–0·95 to –0·41]), and analgesia use (–0·37 [–0·54 to –0·20]), and increased patient satisfaction (1·09 [0·51 to 1·68]), but length of stay did not diff er (SMD –0·11 [–0·35 to 0·12]). Subgroup analyses showed that choice of music and timing of delivery made little diff erence to outcomes. Meta-regression identifi ed no causes of heterogeneity in eight variables assessed. Music was eff ective even when patients were under general anaesthetic. Interpretation Music could be off ered as a way to help patients reduce pain and anxiety during the postoperative period. Timing and delivery can be adapted to individual clinical settings and medical teams.