Acid treatment of the cell-wall D-mannas of Candida stellatoidea strains ATCC 36232 (Type I, A3 strain) and ATCC 20408 (Type II, A2 strain) gave (1----2)-linked beta-D-manno-oligosaccharides (dp 2-5), whereas treatment with alkali gave the (1----2)-linked alpha-D-mannobiose. Conventional acetolysis of the acid- and alkali-treated D-mannan of the A3 strain gave oligosaccharides consisting of (1----2)- and (1----3)-linked alpha-D-mannopyranose residues, similar to those of Candida albicans serotype B strain. Mild acetolysis of the acid- and alkali-treated D-mannan of the A2 strain gave higher oligosaccharides that were digested by the Arthrobacter GJM-1 strain exo-alpha-D-mannosidase. The results of 1H- and 13C-NMR analyses indicated this D-mannan to contain branches with the following structures: beta-D-Manp-(1----2)-alpha-D-Manp-(1----2)-alpha-D-Manp++ +-(1----2)-alpha-D-Manp- (1----2)-D-Man, beta-D-Manp-(1----2)-beta-D-Manp-(1----2)-alpha-D-Manp -(1----2)- alpha-D-Manp-(1----2)-D-Man, and beta-D-Manp-(1----2)-beta-D-Manp-(1----2)-beta- D-Manp-(1----2)-alpha-D-Manp-(1----2)-alpha-D-Manp-(1- ---2)-alpha-D-Manp- (1----2)-D-Man, in common with the D-mannans of C. albicans serotype A strains.