Enteropathogenic E.coli (EPEC) is a major cause of diarrhoea in children under the age of five years. EPEC infections are characterized by attaching and effacing (A/E) lesions that result from bacterial disruption of the microvilli and the subsequent formation of actin-rich platforms called pedestals. Pedestal formation by EPEC requires the bacterium's type three secretion system (T3SS), which injects ~20 effector proteins into the cytoplasm of the host cell. The first EPEC effector, Tir, becomes tyrosine phosphorylated and stimulates actin polymerization through the human Arp2/3 complex. The resulting actin filaments provide a protrusive force that helps remodel the host cell plasma membrane into pedestals. However, it is presently unknown whether EPEC pedestal formation involves manipulation of host processes apart from actin polymerization. Here we demonstrate that EPEC subverts a host process called polarized exocytosis to optimize the efficiency of pedestal formation. Polarized exocytosis is mediated by an octameric complex called the exocyst and the SNARE protein VAMP3. Using an exocytic probe consisting of the SNARE protein VAMP3 fused to GFP, collectively with confocal microscopy imaging we found that exocytosis is upregulated in EPEC pedestals. Moreover, RNAi-mediated deletion of the exocyst proteins Sec3, Sec6, Sec8, Sec10, Exo70, or the SNARE proteins VAMP3 and Syntaxin 4 significantly decreased pedestal formation by EPEC. When both exocytosis and actin polymerization were inhibited by simultaneous depletion of exocyst proteins and the Arp3 component of the Arp2/3 complex, pedestal formation was nearly abolished. Furthermore, by utilizing an EPEC strain lacking the T3SS effector EspH, we identified that EspH plays a critical role in stimulating exocytosis at the sites of pedestal formation. Additionally, we found that EspH contributes to efficient pedestal formation by EPEC. More importantly, by analysing the ultra-structure of the pedestals using scanning electron microscopy (SEM) imaging, I found that EspH has a role in elongation of the pedestals. Collectively, these results suggest that localized expansion of the plasma membrane through polarized exocytosis, mediated by EspH, cooperates with actin polymerization to facilitate efficient pedestal formation by EPEC.