The　chemical　stability　of　spark　plasma　sintering　(SPS)　anisotropic　Nd-Fe-B　magnets　as　well　as　the　conventional　sintered　magnets　in　different　electrolytes　was　studied　by　means　of　anodic　potentiodynamic　polarization　experiments.　In　an　alkaline　solution,　both　magnets　exhibit　evident　passive　behavior,　indicating　that　they　possess　good　corrosion　resistance　in　such　an　environment.　In　saline　and　weak　acid　solutions,　however,　no　passivation　occurred　and　SPS　Nd-Fe-B　has　displayed　a　more　positive　corrosion　potential　E-corr　and　a　lower　corrosion　current　density　I-corr,　than　that　of　the　conventional　sintered　Nd-Fe-B　with　same　composition.　Then,　electrochemical　impedance　spectroscopy　(EIS)　tests　were　carried　out　to　investigate　their　corrosion　kinetics　in　different　solutions.　According　to　Nyquist　and　Bode　diagrams,　a　convenient　equivalent　circuit　was　modeled　and　the　values　of　the　proposed　equivalent　circuit　components　were　calculated.　It　was　found　from　the　EIS　plot　formats　that　the　electrochemical　reaction　of　SPS　Nd-Fe-B　magnets　was　controlled　by　the　step　of　surface　charge　transfer,　i.e.,　activation　polarization　in　alkaline　solution,　while　controlled　by　the　step　of　active　substances　adsorption　on　the　magnet　surface　in　saline　and　acidic　solutions.　Compared　with　conventional　sintered　Nd-Fe-B　magnets,　SPS　Nd-Fe-B　magnets　possess　better　chemical　stability　in　saline　and　weak　acidic　environment.