Diabetic striatopathy is a very rare neurological complication of diabetes. We report the case of an 86-year-old woman with poorly controlled type 2 diabetes admitted to the internal medicine ward for sudden onset of altered sensorium and severe bilateral choreiform and ballistic movements. The precise pathophysiology of this condition is not well understood. Our communication aims to remind clinicians to consider the possibility of diabetic striatopathy when poor-controlled diabetic patients have sudden-onset choreiform and ballistic movements. Moreover, this case suggests the possibility that oxidative and endoplasmic reticulum stress may be involved in this process.