Abstract: Nitrogen cycle is an important research of biogeochemical process. Measurement of total nitrogen (TN) content is a routine experiment in research fields of agriculture, biology, environmental sciences and so on. Kjeldahl method (KM) and Dumas combustion method (DM) are commonly used in measuring TN content in soils. A comparative study on the two methods is conducted by analysis of TN in 10 soil standard samples. The accuracy, precision and correlation of the two methods were compared. The results show that DM and KM have good relativity. DM is better than KM with a precision. However, the results of KM are correctly more than DM in low nitrogen content determination.