A process for producing a phosphate of the lanthanoids is described. The process is based on a two-jet precipitation, starting from separate reservoirs of a rare earth salt solution and a phosphate solution which are introduced simultaneously by separate feedlines into an aqueous acidified initial charge with stirring at a pH of 0.ltoreq.pH.ltoreq.1. After the solutions are added, the pH is raised to a pH of >2 to complete the phosphate precipitation.