Electrospun nanofibers have been found in many applications such as air/water filtration, performance apparel, drug delivery, and scaffold for tissue engineering and started to be integrated in commercial products, which leads to their exposure to environment. Electrospun nanofibrous material is a relatively new material to microorganism in nature and little is known about the biological implication of interactions between electrospun nanofibrous mats and cellular fungal cells. Herein the interaction between electrospun polyacrylonitrile (ESPAN) nanofibrous mat and representative non-pathogenic/pathogenic cellular yeasts ( and ) was investigated. It is demonstrated for the first time that when these cellular yeasts, species of the kingdom fungi, were exposed to ESPAN nanofibrous mat, they exhibited lower growth rate, radical change to morphology, and reduced viability without presence of any chemical antifungal agent. These responses were distinct from the cellular interactions with other forms of PAN materials (e.g. solid film or microfibrous mat). Exploration of mechanism indicated that the interaction between yeast cell and electrospun nanofibrous mat is a complex phenomenon in which both nanofibrous morphology and fiber surface composition/property play significant roles. The inherent anti-yeast and potential anti-fungal functionality of ESPAN nanofibrous mat may make an immediate impact on environmental microorganism and could also benefit the next-generation material design to control microbial growth through solely physical contact.