The structure and morphology of the electrospun nanofiber depend on the parameters such as the physical properties of polymer, the applied voltages, tip to collector distance and ambient condition. Until now, most of studies have been focused on the effects of the above mentioned parameters for electrospinning process. But the study on vacuum conditions in electrospinning process almost not exists. The goal of this study is to investigate the effects of vacuum conditions in electrospinning process. The setup of electrospinning device is installed within homemade vacuum chamber. The polymer jets are ejected from a multi-spinneret connected with a microsyringe pump towards the collector located at fixed distance from the needle tip under a vacuum condition. The nanofiber mats are fabricated using a rotating collector. The visualization and imaging system of electrospinning process are consisted of a green laser devices, microscope, CCD camera and image recording device. During the electrospinning process, the behaviors of nanofiber are visualized and analyzed by this system. The morphologies and dimensions of electrospun fiber mat are measured with SEM. As a final result, the vacuum conditions of electrospinning process influence the behaviors of nanofiber.