The component composition of Cryptococcus albidus and Eupenicillium erubescers alpha-L-rhamnosidases have studied. It was shown that enzymes have a monomeric structure. Enzyme preparations of C. albidus and E. erubescens have similar qualitative but differ in quantitative amino acid composition. alpha-L-rhamnosidase of C. albidus characterised by high amount of histidine, proline, cysteine, methionine in compared with alpha-L-rhamnosidase of E. erubescens. alpha-L-Rhamnosidase of E. erubescens, in contrast to the alpha-L-rhamnnosidase of C. albidus, contained higher levels of lysine, arginine, threonine, alanine, isoleucine, leucine, tyrosine, phenylalanine. It is shown that purified preparations of alpha-L-rhamnosidase C. albidus and E. erubescens contained 5 and 1% carbohydrates respectively. Enzyme preparations differ in quantitative monosaccharide composition, which represented by rhanmose, xylose, mannose, galactose and glucose. Furthermore, alpha-L-rhannosidase C. albidus contained fuicose, whereas alpha-L-rhamnosidase E. erubescens--ribose and arabinose. A significant percentage of hydrophobic amino acids, which is 31 and 34% of the total content, and the presence of the carbohydrate component are essential in stabilization of enzymes molecule.