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The proposed procedure is based on consistent classification of soil organic matter (POM) into two components: primary organic soil matter (POSM), i.e. non-humified portion of POM and humus (H), which have different properties: POSM is characterized by greater or smaller biodegradability and negligible ion-exchanging capacity, despite the fact that it can have sorption capacity. Humus (H) is characterized by very low biodegradability and, on the contrary, very high ion-exchanging capacity. Gradual oxidation with 0.07M K2Cr2O7 solution in 12M H2SO4 at 60°C and monitoring of reaction kinetics of combustion of POM soil samples make it possible to determine the rate constant “k“ of the reaction which is a measure of POSM quality. The higher the “k“ constant the more labile the component is and its quality is better. Its quantity is determined by the final content of carbon after the oxidation completed at 100°C for a period of 45 minutes, which we identified as Cox N. The quantity of humus (H) in the total primary organic matter (POM) can be determined in % as the degree of humification of POM, identified as sH, which is a difference between Cox TOT (quantity of Cox according to ISO/DIS 14 235 by spectrophotometry after the oxidation with 0.27M K2Cr2O7 in concentrated H2SO4 at 135°C for 30 minutes) and Cox N and then divided by Cox TOT. The quality of the humus (H) can be determined from the difference of ion-exchanging capacities of the original soil sample and the soil sample after POM burning with 15% H2O2 in acetic acid environment. A convenient method for the purpose is the Sandhoff method of conductometric titration with volumetric solution of Ba(OH)2.