The invention relates to a method for preparing a 
lead tungstate nano-
powder by using a novel reactant self-emulsifying 
precipitation method. The method includes mixing a 
sodium aliphatate brine solution A and a soluble 
lead salt solution B (containing a trace amount of rare 
metal irons) according to a certain ratio of 
amount of substance, and subjecting the mixture to standing, filtering and washing to obtain a precipitate C; dissolving a certain amount of the C into a hot 
organic solvent to form a transparent 
emulsion D; dropwise adding a certain amount of a 
tungstic acid brine solution into the D to form an 
emulsion E; and cooling the 
emulsion E to the 
room temperature and subjecting the emulsion E to standing, precipitating, washing and 
drying, and calcining the emulsion E in a 
muffle furnace for 4 hours to obtain the 
lead tungstate nano-
powder. According to the method, the prepared 
lead tungstate nano-
powder reaches a nanoscale, the particle size of the lead 
tungstate nano-powder is 10-100nm, the morphology is regular, the distribution is narrow, the particle size of particles can be controlled by changing 
salinity of water phases, the operation is simple and convenient, the requirement on devices is low, and the method is applicable to scale production.