Abstract: The operating conditions of tunnel ventilation system for different-typed poultry houses in China are introduced. The adaptability of an evaporative pad cooling to the climate of China in summer is discussed. The practices show that the air temperature inside various poultry houses in summer can be basically controlled below 28℃or 30℃ and an u-niform distribution of air flow with its velocity of 1. 0 to 2. 0 meters per second and 100 per cent of fresh air for all the birds are provided by using tunnel ventilation and evaporative pad cooling system. Usually, the rate of laying eggs of a layer or a breeding bird could be 5 per cent higher, and the density of birds 10 to 20 per cent increased but the mortality of birds 3 to 5 per cent down. In addition,fewer larger fans used in such a system can save 40 per cent of equipment and electric costs than the conventional system.