The carrier gas process (CGP) based on humidification and dehumidification is a new interesting process (with respect to previous conventional processes such as multistage flash and reverse osmosis) for water desalination. The CGP contains several advantages such as flexibility in capacity, moderate installation and operating cost, possibility of using a wide range of thermal energies (geothermal, solar, recovered, direct fossil fuel, etc.) and simplicity (atmospheric pressure). The aim of this paper is to present the principal and characteristics of this technique based on experimental investigation. The present pilot plant unit consists of two packed columns, humidification and dehumidification, one heat exchanger and one air pre-heater. Most investigators have used solar thermal energy as the source for heating the saline water, but in this work electrical energy was used for heating the air stream. Besides this point most investigators have used a coil heat exchanger for condensation of fresh water but in the present work a packed column was used instead to do the same job. The experimental results of the work that was carried out at Bushehr Port, southern Iran, were: the effect of air pre-heater and coolant water temperatures, air, saline water, recirculating fresh water and coolant water flow rates on the amount of produced fresh water per unit of heat duty and fresh water production flow rate. It was found that the performance of the system strongly depended on the temperature and flow rate of the air pre-heater and the temperature and flow rate of the coolant water. However, it depended weakly on the flow rate of the saline water and fresh water re-circulation. It is expected that the unit would be of great potential for saline water desalination in and areas and isolated islands.