This invention provides a method for preparing hydroxylamine salt by reaction-extraction 'coupled' technique. The method utilizes hydroxylamine hydrochloride and HNO3, H2SO4 or H3PO4 as the reactants to prepare hydroxylamine nitrate, hydroxylamine sulfate or hydroxylamine phosphate. During the reaction, a mixture of amide and diluting agent is utilized as the extraction phase to extract byproduct HCl generated during the reaction to obtain high-concentration hydroxylamine salt mother liquor. Then multi-stage cross-flow or vacuum distillation is performed to obtain concentrated hydroxylamine salt solution or crystal. During the reaction, byproduct inorganic acid can be extracted into the organic phase, which can reduce the amount of inorganic acid in aqueous phase, and break the previous thermodynamic equilibrium limit so that the reaction advances toward the positive reaction direction, and the yield is increased. The method has such advantages as simple process, few buproducts and easy operation, and is suitable for industrialization production.