Abstract: In order to determinate quickly and accurately, and improve the determining efficiency, H₂SO₄-H₂O₂ digestion method for determining plant total nitrogen was improved. H₂O₂ was added only once in digestion process. The coefficient of variation (CV) of the improved method was less than 5%. The recoveries were in the range of 95%-105%. The time of improved method was less 50-80 min than that of the original H₂SO₄-H₂O₂ digestion method. H₂O₂ consumption was saved 0.38 -0.68 mL per sample. Detection results were no significant difference between the two methods. Precision and accuracy met the requirement of detection analysis. The improved method was recommended as digestion method for rapid determining batch plant total nitrogen.