The phosphorus-free deoiling oil prepared by phosphorus-free deoiling powder does not contain phosphorus and is environmentally friendly. The cleaning effect is better than the conventional pre-treatment deoiling process. The service life of the deoiling powder is long and the waste liquid is more easily disposed.The degreasing powder itself has excellent properties, such as wetting, osmosis, emulsification, diffusion, and can be blended with anion and nonionic surfactant, play a role of synergies from the points, and enhance the capacity of net washing, and enables the dirt from being after processing, the stability of diffusion to the processing bath, won't produce the second defiled, achieve complete thoroughly to the oil.The solution is stable and can be used for a long time. The water can be softened with less foam and superior washing performance due to the use of non-ionic surfactant.Because the deoiling powder is an environmental protection, phosphorous free product, it is widely used in metal surface deoiling process.