Additional chemotaxonomic markers are needed to assist in the taxonomic restructuring of the actinomycete genus Micrococcus. Eight of the species currently assigned to the genus Micrococcus have been investigated for the presence of lipoglycan. Macroamphiphilic carbohydrate-containing fractions were purified from phenol extracts by hydrophobic interaction chromatography. The presence of lipoglycans rather than lipoteichoic acids was demonstrated by chemical analysis. Analysis of the carbohydrates present indicated that all the lipoglycans were lipomannans, thereby confirming that lipomannans are distributed throughout the genus Micrococcus. The lipomannans exhibited several different patterns of fatty acid composition, as for the micrococcal whole cells. The presence of lipomannans in both Micrococcus and related genera, notably Rothia and Stomatococcus, may prove a useful marker at the suprageneric level.