Background/Objective: Short hamstring syndrome is common in the general population and can lead to impaired balance, function, and posture, and increased risk of injuries. Local treatments have obtained controversial results, so it is necessary to evaluate the effectiveness of other types of therapy such as osteopathic treatment. To evaluate the efficacy of osteopathic techniques in increasing the elasticity of the hamstring musculature in short hamstring syndrome. Methods: A systematic review of randomised controlled trials was conducted in PubMed, Medline, Cinhal, Scopus, WOS, SPORTDiscuss, and PEDro. The PEDro scale was used to evaluate the methodological quality and the RoB2 for the evaluation of biases. Results: A total of eight articles were selected. Most of the participants were assessed with the Active Knee Extension or Straight Leg Raise tests. The osteopathic techniques used were the muscle energy technique, suboccipital inhibition, and vertebral mobilisations. As for the control interventions, they mainly included passive stretching and placebo. Conclusions: The results suggest that osteopathic techniques are more effective than placebo or other interventions in increasing flexibility in adult patients with short hamstring syndrome. This effect can be explained by neurophysiological (Golgi apparatus, neuromuscular spindle activity, and Hoffmann reflex) and structural factors (dura mater, posture, and myofascial chains). Nevertheless, the evidence suggests that it would be beneficial to incorporate this type of treatment into flexibility improvement programmes.