Basidiomycetes have been part of human culture since the beginning of civilization, used as food resource and for their health beneficial properties. Basidiomycete cell wall polysaccharides, mainly consisting in β-glucans and heteroglucans, often complexed with proteins, are non-starch polysaccharides whose consumption is associated with such benefits, possessing immunostimulant, prebiotic, hypocholesterolemic and hypoglycemic activities. Chemical structure and molecular weight of these polymers are determinant factors for these activities. Since only 1% of Finnish forest mushrooms are collected, this biomass is available for functional dietary fiber production for the nutraceutical market. Extraction procedures influence polymer properties, therefore process development for cell wall polysaccharides requires, as first step, macromolecular characterization of this components. The cell wall polysaccharides from the common Cratarellus tubaeformis have been extracted with hot water, 2% KOH and 25% KOH. After ethanol precipitation, freeze-thawing, and ion-exchange chromatography, the polymers were outlined in their molecular weight, FT-IR spectra, thermogravimetric profile and monomer composition. Utilization of mild alkali solvent resulted in higher yield compared to hot water and strong alkali. Different solvents extracted different cell wall components. The FT-IR indicates higher presence of β-anomeric polymers in the mild alkali fraction, while the presence of α-anomeric signals in the strong alkali fraction suggests release of glycoprotein from the cell wall matrix. Molecular weight of polysaccharides decreased, as expected, as the KOH concentration increased, due to alkali hydrolysis. Mushroom residue is composed of α-chitin and chitosan, probably bound to β-glucans.