In this study, we examined directional self-assembly by electrospun wet fibers. The landing point of the wet fibers was controllable as its trajectory was strictly limited by the adjustment of the parameters of electrospinning. The wet fibers would not stack on the grounded plate in an irregular pattern but in the direction of an electric field in sequence. The preliminary wet fibers deposited and erected on the ground plate to form a controllable circle. The subsequent wet fibers traveled to the top of the circle directionally to organize a mesh tube. The apical circle of the mesh tube was the precise landing point of the subsequent wet fibers. With the wet fibers landing continuously, the mesh tube grew longer and longer. Finally, the controllable circle grew to be the growing mesh tube step by step. We discovered that the mesh tube was assembled by fibers spontaneously in the electrostatic field. In this article, we also try to explain the mechanism of self-assembly and the formation of wet fibers. (c) 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43003.