BackgroundMicroneedling is a promising method for the treatment of acne scars, while the effect of microneedling combined with platelet-rich plasma (PRP) remains unknown. We performed a meta-analysis of controlled studies to compare the efficacy and safety of microneedling treatment with and without additional PRP in patients with acne scars.MethodsRandomized and non-randomized controlled studies were identified by search of Medline, Embase, and Cochrane's Library databases. Results were pooled with a random-effects model, incorporating the possible heterogeneity.ResultsFour randomized and 10 split-face non-randomized controlled studies with 472 patients were included. Compared to microneedling therapy without PRP, combined treatment with microneedling and PRP was associated with increased odds of clinical improvement of >50% in Goodman's qualitative scale [GQS: odds ratio (OR): 2.97, 95% confidence interval (CI): 1.96–4.51, p < 0.001; I2 = 0%], and a significantly improved mean GQS score (mean difference: −0.32, 95% CI: −0.44 to −0.20, p < 0.001; I2 = 0%). Combined treatment was associated with a higher patient satisfying rate (OR: 4.15, 95% CI: 2.13 to 8.09, p < 0.001; I2 = 53%), while the incidence of severe adverse events such as severe erythema (OR: 1.59, 95% CI:.73 to 3.46, P = 0.24; I2 = 0%) and severe edema (OR: 1.14, 95% CI: 0.47 to 2.76, P = 0.77; I2 = 0%) were not significantly different.ConclusionsCombined treatment with microneedling with PRP is more effective than microneedling without PRP for patients with acne scars.