The first case of acute renal infarction in a patient with heavy marijuana smoking is described. The patient had no concomitant previous medical history. There was no evidence of a primary or secondary hypercoagulable state. Underlying neoplasm was excluded. Recovery was associated with normalization of transaminases and lactic dehydrogenase but with a persistent triangular hypoechogenic area in the right kidney. The combination of marijuana-associated alterations in systemic blood pressure due to peripheral vasodilation, functional anemia and an adrenergic effect might have been the cause of the arteria renalis thrombosis in our patient, but the real underlying pathophysiological mechanism still remains unresolved.