Speech disturbances are frequent and potentially disabling in patients with dystonia or chorea due to neurometabolic disorders (DCND), but their precise characteristics are poorly documented. We prospectively studied 29 consecutive patients with DCND. A detailed description of their speech patterns was obtained by using the Frenchay dysarthria assessment test and the apraxia of speech evaluation test of Wertz. Gross motor function and intelligibility were each scored on 5-point scales to identify a possible correlation between the severity of the speech and motor disorders. All the patients were found to have complex speech alterations with combined features of hyperkinetic dysarthria and speech apraxia. We also noted a correlation between the severity of the speech disorders and the motor disorders. These findings have important implications for speech rehabilitation, and may provide new insights into the pathophysiology of dystonia due to neurometabolic disorders.