Abstract: The air side heat transfer and friction characteristics of wavy fin-and-tube heat exchangers with and without hydrophilic coating were studied under dehumidifying conditions experimentally.The effects of hydrophilic coating on air side performance were investigated.The results indicated that the hydrophilic coating could enhance heat transfer when condensed water droplets were too few to form water flow on the fin surface but weaken heat transfer when a large amount of condensed water droplets on the fin surface formed water flow.The pressure drop on the hydrophilic coating surface was lower than the corresponding uncoated surface.A maximum 44% reduction was observed.The proposed correlations of heat transfer coefficient and pressure drop for the heat exchanger with and without hydrophilic coating had a mean deviation of 9.9% and 8.2% from experimental data respectively and could cover 76.6% and 82.8% respectively of the experimental data within the deviation limit of ±15%.