Chromogenic reaction of three hydroxyl phenyl fluorone(THPF) as spectrum probe with antimony was studied in bromination hexadecyl pyridine-emulsifier(CPB-OP) microemulsion medium.When pH=7.01 and the mass ratio of antimony to THPE is 1/3,a stable non-ferrous complex with λmax=460 nm is formed in the microemulsion medium.The molar absorption coefficient of the complex is ε=2.81×106 L·mol-1·cm-1 by bimodal double wavelength spectrophotometry methd,whose precison is 4.43 times of the single wavelength spectrop...