The invention relates to a thermal coupling method and a thermal coupling device for refining vinyl acetate. The thermal coupling method comprises the following steps: enabling kettle liquid of a tower kettle of a crude VAC (vinyl acetate) tower to enter a tube pass of a crude VAC tower reboiler (107), enabling tower top gas of an acetic acid tower to enter a shell pass of the crude VAC tower reboiler (107), returning the heat-exchanged and heated tower kettle liquid of the crude VAC tower to the tower kettle, condensing the tower top gas of the acetic acid tower, and returning the tower top gas to an acetic acid tower reflowing tank (115); enabling kettle liquid of a tower kettle of a refined VAC tower to enter a tube pass of a refined VAC tower reboiler (112), enabling side extract acetic acid steam of the acetic acid tower to enter a shell pass of the refined VAC tower reboiler (112), returning the heat-exchanged and heated tower kettle liquid of the refined VAC tower to the tower kettle, condensing the side extract steam of the acetic acid tower, returning the side extract steam to an acetic acid side extract tank (115), and sending the side extract steam to a synthesis workstation. Through the thermal coupling method and the thermal coupling device, in the vinyl acetate refining process, the heating steam consumption is reduced by 10-20% and the cooling water consumption is reduced by 3-6%; energy and equipment investment is significantly reduced; the production cost of vinyl acetate is reduced.