The invention provides a drying device in a copper foil surface processor. A drying oven is installed on a drying oven frame; guide rolls are arranged at outer side of a copper foil outlet of the drying oven. An air draft mechanism is fixed at the outer side of a copper foil inlet of the drying oven. A liquid squeezing mechanism and an air blade mechanism are respectively arranged at both sides of the drying oven frame. The angle between the drying oven and a horizontal plane is 15 to 30 degrees. Center lines of a support roll and a liquid squeezing roll are in a same vertical plane. Three continuous air outlets located in corresponding positions are arranged on each of corresponding surfaces of an upper air blade and a lower air blade. One end of an upper blower tube is communicated witha side surface of the upper air blade and one end of a lower blower tube is communicated with a side surface of the lower air blade. The other ends of the upper blower tube and the lower blower tube are communicated with a draught distributing box. The draught distributing box is communicated with an air outlet tube of an air blower. By adding the liquid squeezing mechanism, placing the drying oven in an inclined manner and improving the air blade mechanism, good copper foil drying effect is achieved, and phenomenon of oxidation and blackening of the copper foil in storage and application, caused by poor drying effect, can be avoided.