Abstract: To raise the stability of the disperse suspension of fluorescent whitening agent(FWA) C.I.199,the influences of surfactants,electrolytes,pH value on the stability of whitening agent 22E-13 for polyester and 22EC-17 for T/C were investigated through measuring the Zeta potential in their dispersion systems.The results indicated that when an anionic surfactant or a mixture of anionic and nonanionic surfactants is added into the dispersion system,it will improve the system stability significantly.But when electrolytes with high value ion present in the system,its stability deteriorates.In addition,pH value of the system is very important to the stability.