Adherence of Candida has been implicated as the first step in the pathogenesis of oral candidosis, and germ tube formation, a contributory attribute. While chlorhexidine gluconate is by far the most common antiseptic mouthwash prescribed in dentistry, its intraoral concentration fluctuates considerably because of the dynamics of the oral cavity. Hence, the main objective of this study was to investigate the effect of brief exposure to three different sub-therapeutic concentrations of chlorhexidine gluconate on germ tube formation of Candida dubliniensis. Twelve oral isolates of C. dubliniensis were exposed to three different sub-therapeutic concentrations of 0.005%, 0.0025% and 0.00125% chlorhexidine gluconate for 30 min. The antiseptic was removed, and following subsequent incubation in a germ tube inducing medium, the germ tube formation of these isolates was quantified microscopically. When compared with the controls, brief exposure to 0.005%, 0.0025% and 0.00125% chlorhexidine gluconate suppressed the ability to form germ tubes by 76.53% (P < 0.01), 49.17% (P < 0.01) and 3.45% (P > 0.05) respectively. These findings imply that brief exposure to sub-therapeutic levels of chlorhexidine gluconate may modulate germ tube formation of C. dubliniensis, thereby suppressing its pathogenicity in vivo.