The aim of this study was to examine the effects of transcutaneous electrical nerve stimulation on spasticity in patients with multiple sclerosis. The study was carried out in the Hacettepe University School of Physical Therapy and Rehabilitation. The subjects in the study were 10 clinically definite, primary and secondary progressive type multiple sclerosis outpatients with mild to moderate spasticity in the plantar flexor muscles of the ankle. Stimuli of frequency 100 Hz and pulse width 0.3 msec were used 20 minutes per day for 4 weeks. Patients were assessed by electromyography, Modified Ashworth Scale, and Ambulation Index. Electromyograpby was performed before and after the daily treatment of spastic muscles with transcutaneous electrical nerve stimulation in order to assess the effect on muscle relaxation. The Modified Ashworth Scale and Ambulation Index were used before and after 4 weeks' treatment. After 4 weeks of treatment, there were statistically significant reductions in spasticity of both extremities as assessed by myoelectric activity and the Modified Ashworth Scale (P < 0.05). Ambulation Index level was not improved significantly (P > 0.05).