Following stroke, hand edema on the affected side is a common complication. In previous studies, the effects of treatment for edema has had limited effectiveness, indicating that a novel treatment for edema of the affected hand would be required. In this pilot study, we clarified that venous return in the affected arm was promoted by handgrip exercising with the non-affected hand and that it was safe. Although using the affected arm for any activity is generally difficult for patients with hemiplegia, it is easy for them to move the non-affected hand. Hence, further research is necessary to confirm and expand upon the results of this study.