Due to the fact that nine elements，vanadium(V)，chromium(Cr)，nickel(Ni)，cobalt(Co)，arsenic(As)，cadmium(Cd)，antimony(Sb)，thallium(Tl)，and lead(Pb)，have been listed as toxic and harmful substances in fertilizers and are required to not exceed their limits，the existing national standard testing methods for toxic and harmful element in fertilizers are complex，this article established a method of microwave digestion combined with inductively coupled plasma mass spectrometry(ICP-MS)to determine the nine toxic and harmful elements in fertilizers，in order to improve the requirements of fertilizer detection methods.Different types of fertilizers sold in the market in Hebei Province were selected as experimental samples，microwave digestion pre-treatment technology was used to digest the samples，instrument operating parameters were optimized，and 73 germanium(Ge)，103 rhodium(Rh)，and 209 bismuth(Bi)were used as internal standard elements to determine 9 elements in fertilizers using ICP-MS.The results showed that the 9 toxic and harmful elements had a good linear relationship，with a recovery rate of 91.09%-105.43% and a relative standard deviation(n=6)of 1.28%-7.40%.The detection limits were 1.76，10.64，35.87，3.17，0.43，1.50，3.78，4.28 and 180.47 μg/L.In conclusion，the tested fertilizers all met the requirements of national standards，and this method was highly sensitive，simple，and fast，suitable for the determination of 9 toxic and harmful element in fertilizers.