The electrospinning technique has attracted significant research attention because of its various potential applications and simplicity of manufacturing fibers of diameter from several micrometers to nanometer range. However, the methods for controlling the shape, structure, and uniformity of electrospun fibers have not yet been fully investigated. In this research electrospinning instabilities, such as cyclical electrospinning fluctuation and multi-jet ejections, which are closely related to the corresponding nanofiber deposition, were investigated for various polymer solution concentrations. The cyclical electrospinning fluctuation was evaluated with an image analysis program integrated with an image acquisition system that we developed. Two different drop size fluctuations of the cyclical process of the drop formation were observed.