In the proposed work, a novel T-Shaped Source/Drain Extension (T-SSDE) Gate Underlap Gate All Around (GAA) MOSFET is presented and its performance is compared with that of corresponding Conventional Gate Underlap GAA MOSFET using ATLAS-3D device simulator. A quantitative study of main figure of merits (FOMs) for T-SSDE Underlap GAA has been carried out at different Gate Underlap lengths. It is shown that in T-SSDE, short channel effects (SCEs) are suppressed due to enhanced carrier transport efficiency. The results show an improvement in drain current, I-on/I-off ratio, transconductance, high unity-gain frequency f(T) and superior analog/RF performance as compared to conventional Gate Underlap GAA MOSFET, thus, making it a better substitute of conventional Underlap Gate GAA devices for faster switching and low power applications. (C) 2014 Elsevier Ltd. All rights reserved.