Abstract: In this paper,lauramide was synthesized by a series of reactions and the raw materials were urea and lauric acid.First,the influence of single factor on conversion rate was investigated,which include the ratio of materials,reaction time and reaction temperature.Then,the reaction conditions were optimized by orthogonal experiments.The results were as follows:The maximum conversion rate of lauramide was 88.52%.Its optimum conditions were that the material ratio was 1∶1,reaction temperature was 170℃,and reaction time was 4h.The product of synthesis was used as the collector for the bauxite samples flotation.Without any dispersants or inhibitors,the results came out as follows:the optimum pH of lauramide was 5,and the better collector dosage was 160g/t,under these conditions,the recovery of Al₂O₃ could be reached 80.85%.