The purpose of this study was to determine the optimal scoring methods for measuring strength of the more-affected hand in patients with stroke by examining the effect of reducing measurement errors. Three hand-strength tests of grip, palmar pinch, and lateral pinch were administered at two sessions in 56 patients with stroke. Five scoring methods were used to present the strength scores. The smallest real difference was used to provide information on the measurement error. The smallest real difference percentage was used to compare the effect on minimizing the error. Using mean score of tests for nonspastic patients carried out at least twice was found to be advisable to minimize measurement errors in the grip, palmar pinch, and lateral pinch tests. However, the use of hand-strength tests for patients with spasticity is limited because of the relatively high measurement errors.