The yeast spore wall has several features that are not observed in the vegetative cell wall.Using the unique features, we are trying to develop practical applications of yeast spores.Yeast spore wall has a multilayer structure.Its first and second outermost layers are composed of dityrosine and chitosan, respectively.Chitosan known as a unique polysaccharide is an absorptive material to remove wastes from the environment.Using Cu2+ as model heavy metal ion, we tested whether yeast spores could absorb heavy metals.