Аннотация:Natural humic materials possess enormous structural heterogeneity. To overcome this problem, the humiclike products of phenolic copolymerization are frequently used as their synthetic analogues. However a direct analysis of molecular compositions of the synthetic products shows heterogeneity that not allows us to obtain complete structural information. Thus, we present another approach to obtain structural information of natural humic substances. Labeling of humic substances by skeletal H/D exchange enable to determine kind and quantity of protons in HS. Such information will allow to develop targeted synthesis of low dispersed structure analogues of HS. We anticipate our results to be a starting point for systematic studies on skeletal isotopic exchange in humic substances and on molecular adequacy of the humic-like materials.