This study deals with 60 patients with muscle spasm after the lesion of upper motor neurone. Thirty patients were treated by battery operated TENS unit, which produce biphasic impulses, with possibility of individual determination of impulse duration (0.05-0.25 msec), frequency (2-100 Hz) and intensity (0-80 mA). The electrodes were put on the motor points of m. tibialis anterior and m. extensor digitorum. The parameters of stimulation where determined individually, using the impulses that elicit dorsal flexion of the ankle joint and fingers. In the control group, consisted of 30 patients, passive exercises were performed (increasing range of motion, stretching of the agonistic and antagonistic muscles). At the end of the research, the authors report statistically significant decrease of muscles spasm in patients treated by TENS (p < 0.05), as well as improvement of the passive range of motion in ankle joint in both groups. Reducing of the muscle spasm is more pronounced if longer period of stimulation is applied.