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The aim of the research was to improve the efficiency of soil pretreatment for ion-selective electrode (ISE) based soil nitrate-nitrogen detection. Modern experimental apparatuses for soil sample pretreatment, such as microwave, high-speed centrifuge and high-speed vortex oscillator, were validated to replace the traditional pretreatment tools. The single factor test was conducted. Four influencing factors, including microwave time, shaking time, centrifugation rate and time, were selected and optimized. The analysis of variance was applied to analyze the results of orthogonal experiments. The optimized parameters of ISE based soil rapid pretreatment process were obtained as microwave drying time of 9 min, high-speed vortex time of 40 s, centrifugal speed of 1 000 r/min and centrifugal time of 60 s. With the optimized parameters，the validation experiment of 59 soil samples indicated that the mean relative error of the rapid pretreatment and root mean square error were 7.48% and 7.91 mg/L, respectively. The rapid pretreatment time was less than 15 min for a sample.