Critical care practice guidelines identify a lack of clear evidence on the effectiveness of massage for pain control. To assess the effect of massage on acute pain in critically and acutely ill adults post-thoracic surgery. Medline, Embase, CINAHL, PsychInfo, Web of Science, Scopus and Cochrane Library databases were searched. Eligible studies were randomized controlled trials (RCTs) evaluating the effect of massage compared to attention control/sham massage or standard care alone on acute pain intensity post-thoracic surgery. Twelve RCTs were included. Of these, nine evaluated massage in addition to standard analgesia, including 2 that compared massage to attention control/sham massage in the intensive care unit (ICU), 6 that compared massage to standard analgesia alone early post-ICU discharge, and 1 that compared massage to both attention control and standard care in the ICU. Patients receiving massage with analgesia reported less pain (0–10 scale) compared to attention control/sham massage (3 RCTs; N = 462; mean difference −0.80, 95% confidence interval [CI] −1.25 to −0.35; p < 0.001; I2 = 13%) and standard care (7 RCTs; N = 1087; mean difference −0.85, 95% CI −1.28 to −0.42; p < 0.001; I2 = 70%). Massage, in addition to pharmacological analgesia, reduces acute post-cardiac surgery pain intensity.