A humidification-dehumidification desalination unit was built to study the effect of different operating parameters on the unit performance in the range of inlet water temperature of 33 o to 55 o C. The productivity of the unit and energy consumption are evaluated under various operating parameters. It is found that air velocity, inlet water temperature and droplet residence times are the most effective parameters on the unit productivity. At different operating conditions, the ratio of the energy consumed in the production of condensation or evaporation to the energy input (GOR) and the available energy consumed per unit of condensate or evaporate (SCA) based on condensation rate are strongly depending upon inlet water temperature and air mass flow rate. The unit productivity is approaching 8 kg/h of desalinated water at inlet water temperature of 55 o C which is quite good achievement.