Introductionand objectives: This systematic review summarized the evidence on the effects (benefits and harms) of pulmonary rehabilitation for individuals with acute exacerbations of chronic obstructive pulmonary disease (AECOPD).Material and methodsWe included randomized controlled trials comparing pulmonary rehabilitation to either active interventions or usual care regardless of setting. In March 2022, we searched MEDLINE, Scopus, CENTRAL, CINAHL and Web of Sciences, and trial registries. Record screening, data extraction and risk of bias assessment were undertaken by two reviewers. We assessed the certainty of the evidence using the GRADE approach.ResultsThis systematic review included 18 studies (n = 1465), involving a combination of mixed settings (8 studies), inpatient settings (8 studies), and outpatient settings (2 studies). The studies were at high risk of performance, detection, and reporting biases. Compared to usual care, pulmonary rehabilitation probably improves AECOPD-related hospital readmissions (relative risk 0.56, 95% CI 0.36 to 0.86; moderate certainty evidence) and cardiovascular submaximal capacity (standardized mean difference 0.73, 95% CI 0.48 to 0.99; moderate certainty evidence). Low certainty evidence suggests that pulmonary rehabilitation may be beneficial on re-exacerbations, dyspnoea, and impact of disease. The evidence regarding the effects of pulmonary rehabilitation on health-related quality of life and mortality is very uncertain (very low certainty evidence).ConclusionOur results indicate that pulmonary rehabilitation may be an effective treatment option for patients with AECOPD, irrespective of setting. Our certainty in this evidence base was limited due to small studies, heterogeneous rehabilitation programs, numerous methodological weaknesses, and a poor reporting of findings that were inconsistent with each other. Trialists should adhere to the latest reporting standards to strengthen this body of evidence.RegistrationThe study protocol was registered in Open Science Framework (https://osf.io/amgbz/).