Recent investigations suggested possible formation of the vortical structures in the intraglottal region during the closing phase of the phonation cycle. Vortical regions in the flow field are locations of negative pressure, and it has been hypothesized that this negative pressure might facilitate the glottal closure and thus affects the vibration pattern and voice production for high subglottal pressures. However, it is unclear whether the vortex-induced negative pressure is large enough, compared with vocal fold inertia and elastic recoil, to have a noticeable effect on glottal closure. In addition, the intraglottal vortical structures generally exist only for a small fraction of the closing phase when the glottis becomes divergent enough to induce flow separation. In the current work, oscillation of the vocal folds and the flow field are modeled using a non-linear finite element solver and a reduced order flow solver, respectively. The effect of vortical structures is modeled as a sinusoidal negative pressure wave applied to vocal fold surface between the flow separation point and the superior edge of the vocal folds. The effects of this vortex-induced negative pressure are quantified at different conditions of vocal fold stiffness and subglottal pressures. [Work supported by NIH.]