High-performance Nd-Fe-B magnets are widely needed in various fields. The purpose of studying Nd-Fe-B nanometer magnetic powder is that the coercivity of the powdered magnets is the largest at the single domain size. The preparation of nanoparticles by the chemical method can better control the microstructure and grain size. Moreover, metal salts as precursors and simplified process routes can significantly reduce costs and energy consumption. In this review, several popular chemical methods for synthesizing Nd-Fe-B nanoparticles were reported, including sol-gel, auto-combustion, microwave-assisted combustion, thermal decomposition, and mechanochemical method. The preparation process and reaction mechanism of these methods were discussed. Finally, the relationship between microstructure and magnetic properties of Nd-Fe-B nanoparticles prepared by different chemical methods was summarized and some future trends and perspectives in the magnetic research areas were submitted.