The Modified Modified Ashworth Scale (MMAS) is a clinical test for the measurement of spasticity. The aim of the present study was to examine the validity of the MMAS in patients with wrist flexor spasticity after stroke. 27 adult patients (14 women and 13 men) with first ever stroke resulting in hemiplegia with a mean (SD, range) age of 57.9 (11.6, 37-75) were included in the study. The outcome measures were the MMAS for the clinical assessment of spasticity, the Hslope/Mslope (Hslp/Mslp), and the H(max)/M(max) ratio for the neurophysiological evaluation. The mean of the Hslp/Mslp and the H(max)/M(max) were higher in patients with worse MMAS grades but the differences were not statistically significant. There was a significant positive correlation between the MMAS scores and Hslp/Mslp ratio as the new index of alpha motoneurone excitability or traditional index of H(max)/M(max) ratio (r = 0.39, p = 0.04). It is concluded that the MMAS to be a valid measure of spasticity after stroke.