In this work, the thin layer drying behavior of dredged sludge from Dian Lake by convective drying methods was investigated. The results showed that the Modified Page-I model was more suitable for thin-layer drying of dredged sludge. The values of the diffusion coefficients at each temperature were obtained using Fick's second law of diffusion, and it was varied from 6.472x10(-9) to 1.143x10(-8) m(2)/s when the temperature was changed from 100 to 160 degrees C for the dredged sludge of 10 mm. When the thickness was changed from 5 to 20 mm, the diffusion coefficients were varied from 4.036x10(-9) to 2.648x10(-8) m(2)/s at 140 degrees C. The activation energy of moisture diffusion was 13.1 kJ/mol.