QUESTIONS: In adults with a burn injury, do non-invasive therapies improve pain and burn scar pruritus, elasticity and vascularisation? Are any effects maintained beyond the intervention period? DESIGN: Systematic review of randomised trials with meta-analyses. PARTICIPANTS: Adults with burn scars. INTERVENTION: The experimental intervention was a non-invasive (ie, non-surgical or non-pharmacological) therapy applied to the burn scar. OUTCOME MEASURES: Pain intensity, pruritus intensity, elasticity and vascularisation. RESULTS: Fifteen trials involving 780 participants were included. The results indicated a beneficial effect on pain intensity on a 0-to-10 scale after massage (MD -1.5, 95% CI -1.8 to -1.1), shockwave therapy (MD -0.8, 95% CI -1.2 to -0.4) and laser (MD -4.0, 95% CI -6.0 to -2.0). The results indicated a beneficial effect on pruritus intensity on a 0-to-10 scale after massage (MD -0.4, 95% CI -0.7 to -0.2), shockwave therapy (MD -1.3, 95% CI -2.3 to -0.3) and laser (MD -4.8, 95% CI -6.1 to -3.5). Massage, shockwave therapy and silicone produced negligible or unclear benefits on scar elasticity and vascularisation. The quality of evidence varied from low to moderate. CONCLUSION: Among all commonly used non-invasive therapies for the treatment of burn scars, low-to-moderate quality evidence indicated that massage, laser and shockwave therapy reduce pain and the intensity of scar pruritus. Low-to-moderate quality evidence suggested that massage, shockwave therapy and silicone have negligible or unclear effects for improving scar elasticity and vascularisation. REVIEW REGISTRATION: PROSPERO (CRD42021258336).