A cooling system and method for a paper coating device, especially for cooling a coating blade of the coating device and a coating color to be coated on paper web, whereby a streaking and/or bleeding phenomena caused by accumulation of the coating color at the end of the coating blade are effectively inhibited. The cooling system comprises a cooling means equipped at a back surface of the coating blade, interconnecting hoses for communicating coolant to the cooling means, a circulating unit, and a heat-exchanging unit.