Manganese is one of the necessary trace elements in human body. The content of exchangeable manganese in soil directly affects the absorption of manganese by plants，and then affects human health through the food chain. In this paper，1 mol/L ammonium acetate solution is used as the exchangeable manganese extractant，the soil samples are pretreated in a high-precision constant temperature shaking box，and the samples are analyzed and tested by inductively coupled plasma emission spectrometer. By optimizing the pretreatment operating conditions，an accurate，reliable，high-precision and stable detection method is established. The detection limit of this method is 0.104 mg/kg，The relative standard deviation (n=12)of certified soil standard samples is 1.11%～2.45%. This method is compared with LY/T 1263—1999 to analyze the actual soil samples，and the relative deviation is less than 5%，which meets the quality control provisions of the standard method and the sample analysis requirements. This method is very suitable for laboratory promotion and use.