Abstract: Nonylphenol (NP for short) and diethanolamine were used as raw materials to synthesize one cationic and four amphoteric asphalt emulsifiers. The structure of emulsifiers was investigated by FT-IR. The effective content of reaction products was determined by chemical titration. Emulsifiers synthesized were used for preparing emulsified asphalt. The performance was tested, including emulsifying effectiveness, storage stability, mixing stability, normal viscosities, asphalt content, residues on screening and the property of wrapping coarse aggregate. The results demonstrated that the four emulsifiers have good properties. One of them can be used as a moderate-setting asphalt emulsifier; the others can be used as slow-setting asphalt emulsifiers.