New aerated foam drilling fluid, using a special plant fiber named KWS as fluid material, not only has the characteristics of low density, high ability of removing cuttings and lower use of water, but also has the perforation of rejecting of the Na+’s and Ca2+’s affection. By application of this drilling fluid, drilling engineers dealt with the leakage problems successfully in Xinjiang and it has a bloom application in west part of China where is short of water.