Choosing the main components of a liquid detergent:surfactants is a key factor in confecting liquid detergent.Inview of that affect washing,the author puts forward several current principles in chooing the main components of a liquid detergent, and summarizes methods of choosing emulsification agent,a key factor that influeuces washing,and its working condifions are also given.Main components which have been chosen must be optimized to test the synergism. At last, practical and specific surfactants are obtained.