To improve phosphate flotation especially with regard to reduction of consumption of collector the relationship between the flotation performance of phosphate collectors and their adsorption behaviour was evaluating using a variety of techniques including Crystal Microbalance with Dissipation technique (QCM-D), a highly sensitive method for in-situ surface characterization. The adsorption of collectors on the surface of hydroxyapatite was primarily characterized using QCM-D. Additionally, the collectors were evaluated by zeta potential and FTIR analysis. The flotation performance of the collectors was evaluated using a laboratory mechanical flotation cell at different process parameters such as pH, Collector dosage, diesel dosage and flotation time and using two collectors: a commercial plant collector (I) and a refined tall oil fatty acid (II). The QCM-D dates showed that collector II adsorbed on phosphate surface more readily and produced stronger hydrophobicity and bette flotation performance then collector I. By means of zeta potential measurements and FTIR analysis the chemisorption and surface precipitation mechanisms of collector II were demonstrated on the surface of hydroxyapatite.