The Cyber Musical Instrument with Score (Cymis) was invented as an electronic musical instrument by hich everyone, including musical naïve persons, could enjoy playing easily and effortlessly. In this tudy, we tried to introduce the Cymis for the upper limb paralysis training of brain disease patients. For roceeding a year of the experiment, we modified the original Cymis to be available in the clinical ituation (medical Cymis). Then we performed the intervention using the medical Cymis to two chronic troke patients with upper limbs paresis. We carried out upper limb training of music performance total 0 times. As the results, significant improvement was observed in motor function of paretic limbs. In ddition, the increase of the frequency of the use of paretic hand and the distance of walking was also bserved. It was supposed that the medical Cymis is useful for the rehabilitation of upper limb’s paralysis ue to cerebrovascular accidents even in its chronic phases.