Previous studies have shown that aerobic exercise is an effective way to improve symptoms of Parkinson's disease (PD). The aim of this study [PROSPERO CRD42022340730] was to explore the effects of aerobic exercises on balance, gait, motor function, and quality of life in PD patients. Searches were performed in PubMed, Web of Science, and EBSCO electronic databases. The Cochrane risk assessment tool was used to evaluate the methodological quality of the included literature. From 1287 search records initially identified, 20 studies were considered eligible for systematic review and meta-analysis. There was a significant effect of aerobic exercise on improving timed up and go test [standardized mean difference (SMD), -0.41 (95% CI, -0.61 to -0.22), p < 0.00001], Berg Balance Scale [0.99 (95% CI, 0.76 to 1.23), p < 0.00001], stride/step length [0.32 (95% CI, 0.03 to 0.61), p = 0.03], gait velocity [0.49 (95% CI, 0.20 to 0.78), p = 0.0009], Unified Parkinson's Disease Rating Scale Part-III [-0.40 (95% CI, -0.55 to -0.24), p < 0.00001], and 6-minute walking test [0.35 (95% CI, 0.13 to 0.56), p = 0.002] in people with PD, but not in step cadence [-0.08 (95% CI, -0.43 to 0.27), p = 0.65] and Parkinson's Disease Questionnaire-39 [-0.113 (95% CI, -0.39 to 0.13), p = 0.32]. Aerobic exercise had beneficial effects in improving balance, gait (velocity and stride/step length), and motor function in PD patients. However, aerobic exercise had no significant associations with the step cadence and quality of life in PD patients.