This paper describes a high performance neural processor by using a Network on Chip (NoC) architecture to solve the interconnection and performance problems in hardware neural networks. The proposed NoC-based neural processor is composed of 20 tiles in 45 2-D array, and each tile includes a Process Element (PE) and a packet switched router. In each PE, four neurons are implemented to achieve low communication load. The network is 2D torus topology, and it has a 32 G/s bandwidth and asynchronous clocking system. Our proposed neural processor is designed using 90-nm CMOS technology with one Poly and nine metals, and its performance is evaluated. As a result, it can achieve over 3.1 G Connection Per Second (CPS) of performance while power dissipation is 1.1317 W at 1.2 V supply-voltage and 25 mm2 chip area. Compared with the other existing hardware neural networks, the proposed processor can achieve low communication load and high performance, and it is reconfigurable and extendable.