Restless leg syndrome (RLS) can develop secondary to various medical conditions. Some medications, as well as some opioid withdrawal, are known to induce RLS. Opioids modulate the dopamine system via their receptors and change the sensitivity to dopamine. Abrupt withdrawal of opioid may cause an endogenous opioid deficit state and disturb the dopamine system, which can lead to a transient dopamine dysfunctional state such as RLS. We reported a man with secondary RLS after acute withdrawal of the opioid, oxycodone, which has not been previously reported.