The purpose of this study was to investigate the adsorption of [3H]-thymidine labeled oral microorganisms to porous type calcium carbonate (PCC) beads in a buffer containing human parotid saliva and to PCC combined chewing gum sheets. Adsorption rates of Streptococcus sobrinus B13 and 6715, Streptococcus mutans MT8148R and Actinomyces naeslundii T14V with PCC were significantly higher than those with calcium carbonate (CC) beads (p < 0.01). Adsorption rates of S. sobrinus, S. mutans and A. naeslundii with PCC combined chewing gum were significantly higher than those with CC combined chewing gum (p < 0.01). The present results suggested that the chewing gum containing PCC may be able to exclude oral bacteria, including cariogenic and periodontopathic bacteria, for prevention of dental caries and periodontal disease.