Zinc has antimicrobial activity and zinc salts including zinc chloride ($ZnCl_2$) have been used for the control of oral malodor. In this study, we hypothesized that pyrrolidine dithiocarbamate (PDTC), a zinc ionophore, may enhance antimicrobial efficacy of $ZnCl_2$. The bactericidal effectiveness of $ZnCl_2$ alone (0.5-8 mM) or in combination with PDTC (1 or $10{mu}M$) was evaluated by in vitro short (1 h) time-killing assays against Fusobacterium nucleatum and Porphyromonas gingivalis. Only a slight viability decrease was observed with $ZnCl_2$ or PDTC alone after 1-h incubation. By contrast, combination of $ZnCl_2$ and PDTC could achieve a more than 100-fold viability reduction compared with $ZnCl_2$ or PDTC alone in F. nucleatum and P. gingivalis. Therefore, PDTC greatly enhanced the bactericidal activity of $ZnCl_2$ against the oral malodor-producing bacteria. These results suggest that use of PDTC may be useful for enhancing bactericidal activity of anti-malodor regimens of zinc salts.