Chlorhexidine gluconate and hexitidine have been used in many oral health care products as antiplaque and antigingivitis agents. Based on the clinical observations and the plaque and gingivitis scores, chlorhexidine gluconate has been reported to be a better agent. In this study, the anti-adherence properties of chlorhexidine gluconate and hexitidine on individual bacteria strains isolated from a 3-hour plaque (Streptococcus sanguis, Streptococcus mitis 1 and Actinomyces sp.) and on a whole 6-hour plaque culture were determined and compared. The study showed that chlorhexidine gluconate inhibited almost 100 % the adherence of the individual bacteria strains and 87.7 % the adherence of a whole 6-hour plaque culture to the saliva-coated glass surface. Hexitidine appeared to be more selective in its effect. It was shown to inhibit the adherence of S. sanguis and Actinomyces sp. to saliva-coated glass surface by 86.5 % and 51.4 % respectively. Its effect on the S. mitis 1 strains is comparable to that of a whole 6-hour plaque culture where inhibition to adherence were less than 4 % for both.