Studied by the histochemical fibrin slide technique sections of normal cornea of man and several mammals are fibrinolytically inactive. After corneal injury plasminogen activator can be demonstrated in relation to the epithelial or endothelial linings and in detached epithelial or endothelial cells. In general, severely degenerated cells show the highest fibrinolytic activity. In fragments of corneal epithelium a weak protease effect could be demonstrated. The possible origin of the plasminogen activator and its possible physiological functions are discussed.