The airside heat transfer and pressure drop characteristics of slit fin-tube heat exchanger with hydrophilic coating were studied experimentally under dehumidifying conditions.The effects of inlet air relative humidity on airside performance were investigated.The Nusselt number and friction factor f were applied to describe airside heat transfer and pressure drop characteristics.The results show that Nu increases with the rise of inlet air relative humidity,while the change of friction factor f is not obvious.The effect of inlet air relative humidity on Nu becomes more remarkable with the decrease of waterside temperature.Inlet air relative humidity has little effect on sensible heat exchange of airside.