This paper presents the analytical and experimental analysis of a membrane based air-dehumidification system for handling the latent loads efficiently. This is important for tropical countries like Singapore where the humidity content of ambient air is high and therefore, air conditioning systems need to handle large latent load. A detailed COMSOL simulation model was set-up in order to simulate the water diffusion through the membrane. Experimental results from a real size membrane dehumidification unit are used to validate the mathematical model. Our investigations show that the moisture content of ambient air may be reduced by more than 5 g per kg of air if the dehumidification process is driven by the gradient between the water content of ambient air and the water content of exhaust air form air-conditioned spaces. With the exception of low electricity requirement for air transport, there is no electric energy consumption in the system. Therefore, the membrane system discussed in this paper is an efficient and alternative way of air dehumidification for air conditioning applications, potentially reducing the electricity consumption of air conditioning system in tropics.