In this paper, it has been analyzed how transport characteristics is influenced on gate oxide properties in the subthreshold region as nano structure FinFET is fabricated. The analytical model is used to derive transport model, and Possion equation is used to obtain analytical model. The thermionic emission and tunneling current to have an influence on subthreshold current conduction are analyzed for nano-structure FinFET, and subthreshold swings of this paper are compared with those of two dimensional simulation to verify this model. As a result, transport model presented in this paper is good agreement with two dimensional simulation model, and this study shows that the transport characteristics have been changed by gate oxide properties. As gate length becomes smaller, funneling characteristics, one of the most important transport mechanism, have been analyzed.