Purpose Investigate and measure the effects of electrostimulation on the orofacial musculature and on the chewing, breathing and swallowing functions of individuals with Down syndrome. Methods Study participants were 16 individuals with Down syndrome (six males and 10 females) from an institutional extension project aged nine to 25 years. Speech-language pathology assessment was performed using the protocol of Orofacial Myofunctional Evaluation with Scores (OMES) pre- and post-intervention. This protocol comprised eight weekly electrostimulation sessions. Functional Electrical Stimulation (FES) current was used at a frequency of 10Hz in warm-up and 30Hz in application, intermittent stimulation (cycling pulses) with ON-time of 5s and OFF-time of 10s common to both stages, and pulse width of 200μs in warm-up and 250μs in application. Results Significant differences were observed between pre- and post-application of FES regarding cheek appearance (flaccidity and arching), tongue mobility (right and left laterality), and musculature behavior during performance of functions of the stomatognathic system: respiration, deglutition (lip behavior), and mastication (bite and trituration). Conclusion Effects of electrostimulation associated with masticatory training of the masseter muscles were statistically identified, with functional gains in chewing, breathing and swallowing performance in individuals with Down syndrome.