We have developed a method to separate phosphor waste which is a mixture of several kinds of phosphors into each species of phosphor by using a high magnetic field gradient separation method. Measurement of magnetic susceptibility of phosphors revealed that each phosphor has different magnetic susceptibility. Green phosphor, LaPO₄: Ce,Tb (LAP), shows one order of magnitude higher magnetic susceptibility than other phosphors. By choosing an appropriate dispersant and optimizing operation procedure, the efficiency for the separation was increased. As a result, LAP was recovered as a magnetic product in the separation column with above 80 % of the concentration by one step separation. It was also confirmed that separation of other phosphors having smaller difference in magnetic susceptibility could be achieved.