The invention provides a method for preparing a NaP molecular sieve from white mud as a raw material and the NaP molecular sieve. The method comprises the steps of (1) preparing a structure-directing agent; (2) preparing a silicon source and an aluminum source, namely extracting the white mud by using a sodium hydroxide solution, filtering and collecting filtrate for later use; (3) preparing silica-alumina gel, namely adding sodium metaaluminate and deionized water to the filtrate until the molar ratio of SiO2 to Al2O3 in the system is (2-3):1 and the molar ratio of Al to H2O is 1:(360-495), adjusting the pH value of the system to be 10-11, adding the structure-directing agent, stirring evenly and ageing to obtain the silica-alumina gel; (4) crystallizing the silica-alumina gel; and (5) carrying out post-treatment, namely filtering a crystalized product and then washing and drying the filtered product to obtain the NaP molecular sieve. According to the method, the NaP molecular sieve can be prepared by fully utilizing effective silicon and aluminum in the white mud, the waste utilization of the white mud is achieved, the preparation cost of the NaP molecular sieve is reduced and the prepared NaP molecular sieve is good in performance, large in ion exchange capacity and high in economic benefit.