In the paper we compared herein chemical properties of the fungal chitosan prepared according to the own method and the commonly used chitosan made from the crustaceous. The assessment included such parameters as: ash, fiber, fat, Na, K, Ca and Mg content. Inorganic phosphates, molecular weight and deacetylation degree were also determined. Based on these results a number of differences between substances was identified. The differences are related to varied structure that is due to different methods of two types of chitosan production. The difference in viscosity was the most pronounced parameter. It has been proved the viscosity of fungal chitosan was 5 times lower compared to crustaceous chitosan. The fungal chitosan was characterized with higher deacetylation degree (DD) than crustaceous chitosan. The deacetylation process has significant influence on the structure and chemical parameters of the chitosan. The chemical elements content was differentiation. Relatively low concentration of sodium was identified in the fungal chitosan. However, it contained high levels of nitrogen, fiber and fat when compared to the crustaceous chitosan.