Abstract: M-278 and KMF of drainage sediment geochemical standard reference samples were used to evaluate analysis errors of loss on ignition (LOI). Location of the samples in the muffle furnace affected the measured value of LOI distinctly. The effects of organic matter by LOI were dramatically different from that of carbonate. If the sample was placed near the furnace door there would be evident analytical errors. However an empirical coefficient could help to revise the measured value of the two samples near the furnace door. The analytical errors would be diminished by multiplying the coefficient of 1.064. For the standard samples are unavailable the sample KMF was used to test the conclusion further In spite of different content of the organic and carbonate the results were also the same as the former So great attention should be paid to the location of the crucibles when using LOI to estimate organic matter and carbonate content There are not only organic matter and structure water but also carbon dioxide of calcific soil and system error of experiment in the loss on ignition, but the empirical coefficient could only decrease the analytical errors In the experiment the organic matter was destroyed at the temperature of $550^{\circ}\mathrm{C}$ for two hours and the carbonate was decomposed at the temperature of $950^{\circ}\mathrm{C}$ . In order to get the method of revising the experiment errors, the same experiment was repeated three or more times

Key words: loss on ignition, organic matter, carbonate content, adjusting coefficient