Abstract: Combustion-infrared absorption spectrometry is a standard method for the determination of total carbon in soil and sediment. In order to explore the feasibility of developing the elemental analyzer into a standard method for the determination of total carbon in soil and sediment, the research mentioned by this article was carried out. Five representative soil and sediment reference materials were selected and determined by combustion-infrared absorption spectrometry and elemental analyzer. It was shown that RSDs (n=6) of the determined values obtained by combustion-infrared absorption spectrometry were in the range of 1.2%-2.7%, with relative errors ranged from -2.9% to 0.63%, and RSDs (n=6) of the determined values obtained by elemental analyzer were in the range of 0.24%-2.7%, with relative errors ranged from -3.3% to 0.84%. The results of t test for the two methods were satisfied ｜t｜<t_(0.05) and P>0.05, indicating that there was no significant difference between the two methods. Based on these facts that the elemental analyzer was simple, rapid, and suitable for the determination of large quantities of samples, which had high accuracy and precision, so it could be considered as a standard method for the determination of total carbon in geological samples such as soil and sediment.