The objective of this study was to evaluate the efficacy of proprioceptive neuromuscular facilitation (PNF) on range of motion (ROM) gain in young healthy adults. We performed a systematic review of randomized controlled trials and quasi-randomized trials, including young healthy adults. The interventions were: PNF compared with different PNF techniques, control, other muscle stretching exercises and musculoskeletal manipulations. The outcome measures were: articular ROM and adverse effects. The final number of included studies was 46, involving 1,864 adults. There was difference on ROM comparing assisted hold-relax (HR) on diagonal plane to control, based on very low-quality evidence. There was also difference on ROM comparing assisted HR to self-HR; self-contract-relax (CR) to control; assisted CR contract to control; and assisted HR contract to control, based on low-quality evidence. Moderate-quality evidence shows that results differ between self HR and control (SMD: 0.95; 95%CI 0.03, 1.86; I249%; P = 0.16) in terms of ROM gain. When performing the other comparisons, the results were based on low or very low-quality evidence and do not allow to state if PNF is more or less effective than other stretches for improving ROM in healthy young adults. No adverse effects were mentioned.