Ankyloglossia is a pathology of the tongue in which the frenulum appears anchored to the floor of the mouth. The treatment of choice for this pathology is frenectomy, but myofunctional therapy is emerging in recent years as a complement to surgical intervention. This systematic review aims to synthesize the scientific evidence and assess its quality regarding the use of myofunctional therapy in ankyloglossia. The Cochrane Central Register of Controlled Trials, Physiotherapy Evidence Database, Pubmed, Web of Science and Scopus were searched. Study quality was determined using the PEDro scale, STROBE statement and single-case experimental design scale. Eleven studies were selected. Based on the studies included in this review, surgery is more effective than myofunctional therapy, although better results are achieved if both are combined. Improvements have been found in maternal pain, weight gain of babies, duration of breastfeeding, tongue mobility, strength and endurance, sleep apnea, mouth breathing and snoring, quality of life, clenching teeth, myofascial tension, pain after surgery and speech sound production. These findings must be taken with caution because of the small number of articles and their quality. Future clinical trials using larger sample sizes and with higher methodological quality are needed.