Temporomandibular disorders (TMD) negatively affect quality of life, causing pain and restricted jaw movements. This study evaluates the effectiveness of Transcutaneous Electrical Nerve Stimulation (TENS) on TMD patients before orthodontic treatment at the Juarez Autonomous University of Tabasco. A quantitative, quasi-experimental study was conducted with 30 patients who met the inclusion criteria: aged 18 to 65 years, with TMJ pain symptoms, diagnosed with temporomandibular disorders using the Helkimo index, and who had provided informed consent for the study. The range of mandibular movement and the Visual Analog Scale (VAS) were measured to record values before therapy. The electrodes of the TENS therapy were positioned on both sides of the jaw in the preauricular area and the masseter muscle, the therapy was administered for 40 minutes, utilizing a frequency of 2 -4 Hz and a pulse duration of 300 microseconds. Following this, the range of mandibular movement and the VAS were reassessed to evaluate the outcomes., significantly improved maximum mouth opening (37.7 ± 6.4 mm to 44.6 ± 5.88 mm), right laterality (3.86 ± 1.57 mm to 5.43 ± 1.21 mm), left laterality (3.13 ± 1.63 mm to 4.53 ± 1.61 mm), protrusion (4.01 ± 1.7 mm to 5.36 ± 1.32 mm), and pain perception (4.56 ± 2.045 to 2.03 ± 1.5) (P < 0.01). TENS therapy enhances mandibular movement and reduces pain, making it a well-tolerated, non-invasive complementary treatment for TMD.