The paper describes the Low power 32-bit encrypted MIPS processor based on AES algorithm and MIPS pipeline architecture. The pipeline stages of MIPS processor are arranged in such a way that pipeline can be clocked at high frequency and clock gating technique is used for reducing power consumption. Encryption blocks of Advanced Encryption Standard (AES) cryptosystem and dependency among pipeline stages are explained in detail with the help of block diagram. In order to reduce the power consumption, especially for portable devices and security application switching activity is used inside pipeline stages. The design has been synthesized at 40nm process technology targeting using Xilinx Virtex-6 device. The encrypted MIPS pipeline processor can work at 210MHz and power consumption is 1.313W.