A dual slot die coater having a lower slot and an upper slot configured to extrude and apply a coating solution through at least one of the lower slot and the upper slot to the surface of a continuously running substrate, comprising: die blocks comprising a lower die block, a middle die block disposed at an upper portion of the lower die block to form the lower slot between the middle die block and the lower die block, and an upper die block disposed at an upper portion of the middle die block to form the upper slot between the upper die block and the middle die block; a lower manifold that accommodates a first coating solution as a recessed chamber provided in the lower die block or the middle die block and communicates with the lower slot, and an upper manifold that accommodates a second coating solution as a recessed chamber provided in the middle die block or the upper die block and communicates with the upper slot; and a lower air vent installed in the lower manifold region, and an upper air vent installed in the upper manifold region; wherein each of the lower die block, the middle die block, and the upper die block comprises a lower die lip, a middle die lip, and an upper die lip, which respectively forms the front end of each die block, wherein a lower outlet communicating with the lower slot is formed between the lower die lip and the middle die lip, and an upper outlet communicating with the upper slot is formed between the middle die lip and the upper die lip, characterised in that the lower air vent is installed adjacent to a front end of the lower manifold among the ends of the lower manifold without being installed at a lower land portion that is a portion where the front end placed on the lower outlet side and the lower outlet are connected. die blocks comprising a lower die block, a middle die block disposed at an upper portion of the lower die block to form the lower slot between the middle die block and the lower die block, and an upper die block disposed at an upper portion of the middle die block to form the upper slot between the upper die block and the middle die block; a lower manifold that accommodates a first coating solution as a recessed chamber provided in the lower die block or the middle die block and communicates with the lower slot, and an upper manifold that accommodates a second coating solution as a recessed chamber provided in the middle die block or the upper die block and communicates with the upper slot; and a lower air vent installed in the lower manifold region, and an upper air vent installed in the upper manifold region; wherein each of the lower die block, the middle die block, and the upper die block comprises a lower die lip, a middle die lip, and an upper die lip, which respectively forms the front end of each die block, wherein a lower outlet communicating with the lower slot is formed between the lower die lip and the middle die lip, and an upper outlet communicating with the upper slot is formed between the middle die lip and the upper die lip, characterised in that the lower air vent is installed adjacent to a front end of the lower manifold among the ends of the lower manifold without being installed at a lower land portion that is a portion where the front end placed on the lower outlet side and the lower outlet are connected.