During the drying process of sized yarn, the film of sizing agent begins to form from the outpost side of the sized yarn. When the film of sizing agent has formed, drying rate decreases rapidly. In the constant drying rate region, drying rate can be obtained theoretically from the energy balance. Drying rate in the falling-drying-rate region, however, depends on the mass fraction of water at the plastic paste surface and therefore is obtained through the experiments. Predictions of drying rate using the developed empirical correlation show good agreement with the experimental results.