The flotation behaviors of rutile in combined regent system of sodium oleate (SO) and sodium benzohydroxamide (BHA) were studied via pure mineral flotation test. The interactions between reagents, reagents and mineral as well as the effect of the reagent combination on rutile flotation had been investigated through several measurements, including Zeta potential, contact angle, surface tension, UV diffuse reflectance spectroscope, concerning the interface chemistry properties at gas?liquid interface and solid?liquid interface. The results indicated that the reagent addition sequence influenced rutile recovery significantly and the combined use of reagent had a distinct positive-synergistic effect under different pH values. The flotation recovery of rutile and synergistic effect index followed the order: adding BHA prior to SO>pre-mixed before adding>adding SO prior to BHA. The electron-rich double bond in SO may interact with the electron-deficient benzene ring in BHA to form diverse interionic/intermolecular association complexes. The amount of the complex presented as the optimum configuration on mineral surface was critical for the synergistic effect of reagent combination and rutile flotation behavior. The effect of reagent combination on flotation recovery rate agreed well with that on the rutile bandgap width according to the UV diffuse reflectance spectroscope spectrum of rutile sample after interacted with the reagent combination under various conditions.with the electron-deficient benzene ring in BHA to form diverse interionic association complexes. The amount of the complex presented as the optimum configuration on mineral surface is critical for the synergistic effect of reagent combination and rutile flotation behavior. The effect of reagent combination on flotation recovery agree well with that on the rutile bandgap width according to the UV diffuse reflectance spectroscope spectrum of rutile sample after interacted with the reagent combination under various conditions.