Diffusion tensor imaging (DTI) provides quantitative information in the magnetic resonance imaging on the diffusion anisotropy about the integrity of white matter tracts. The aim of this study was to measure diffusion anisotropy and to correlate with upper-limb motor recovery in four chronic hemiparetic patients with thalamic hemorrhage. Fractional anisotropy (FA) was measured in the posterior limb of internal capsules (IC) in the affected side and in the corresponding contralateral normal side before and after 6 week motor training. The correlation between motor recovery of the affected hand and the ratio of FAs of the affected side and the contralateral normal side were investigated. Both FA ratio and motor function significantly increased after the training. A significant correlation was found between motor recovery and FA in the posterior limb of IC. The degree of impairment in diffusion anisotropy of hemiparetic patients might be helpful in prognosis of the motor function.