Proposes an HVAC system which combines chilled ceiling with desiccant cooling, to be used in hot and humid climates where air dehumidification is necessary in order to maintain the indoor air humidity within a comfort zone and to lessen the risk of condensation on chilled panels. The system decouples temperature and humidity control by using desiccant wheel for moisture removal and ceiling panels to control the temperature. Another three systems were viewed to evaluate the system performance and energy savings potential. The systems were: conventional all-air system, all-air system with total heat recovery, and radiant cooling with air handling unit, all seen as typical in Hong Kong office buildings. A building energy simulation code was used to calculate the hourly sensible load, called ACCURACY, and the latent load was predicted by looking at moisture balance in the room. The annual energy consumptions of the four systems were calculated and analysed through hour-by-hour simulations. Compared with a conventional constant volume all-air system, the results indicated that chilled-ceiling combined with desiccant cooling could save up to 44% of primary energy consumption. Also low grade heat of less than 80 deg. C could be used to achieve more than 70% of annual operating hours for desiccant regeneration.