Reconfigurability of a novel spintronics-based MOSFET; "Spin-transfer- Torque-Switching MOSFET (STS-MOSFET)" was successfully realized in the transport properties. The device showed magnetocurrent (MC) and write characteristics with the endurance of over 105 cycles. It was clarified that the read and write characteristics (i.e., MC ratio and write voltage) can be improved by choosing connection configurations of the source and the drain in the STS-MOSFETs. Large scale circuit simulations for various circuits in FPGA revealed that the critical path delay is significantly improved by using the STS-MOSFETs. The overall properties of the STS-MOSFETs show great potentialities for future reconfigurable integrated circuits based on CMOS technology.