Abstract: Anterior cruciate ligament reconstruction (ACLR) has a high incidence among sports players, and one important side effect of the surgery is graft donor site morbidity. Although some evidence suggests that application of platelet-rich plasma (PRP) during ACLR reduces pain and improves knee function, it is not a universal finding. To perform a meta-analysis of previous studies testing the effects of PRP on donor site morbidity after ACLR. Systematic review and meta-analysis. We reviewed PubMed (Medline), Web of Science, Embase, Scopus, and Cochrane databases to find studies testing the effects of PRP on the donor site of ACLR autograft. After identifying 4 studies, we conducted 2 meta-analyses, 1 for the effects of PRP on pain, assessed by visual analog scale (VAS), and the other for the functional knee scores. We also tested the ability of time after ACLR to predict the PRP-related reduction of pain. In the 4 studies identified, 157 patients were analyzed. Although the VAS score was lower with PRP at 6 months (raw mean difference [RMD], -0.97 [95% CI, ?1.59 to ?0.36]; P = .001) and 12 months (RMD, ?0.61 [95% CI,?1.02 to ?0.21]; P = .003), the effects of PRP disappeared at 24 months (RMD, ?0.08 [95% CI,?0.38 to 0.22]; P = .586). A univariate regression analysis reinforced the ability of time after ACLR to predict the PRP-related reduction of VAS pain score (r2 = 0.98). However, knee function after ACLR was not improved by the use of PRP (standardized mean difference, 0.71 [95% CI,?0.17 to 1.60]; P = .114). PRP applied to a bone-patellar tendon-bone donor site could reduce knee pain within a year, and this reduction had a correlation with time, meaning that the effect of PRP decreased with time after surgery. However, pain reduction did not reach clinical relevance and did not lead to better functional knee scores Ver menos