In this work, we obtain an area proficient composite field arithmetic Advanced Encryption Standard (AES) Substitution (S) byte and its inverse logic design. The size of this design is calculated by the number of gates used for hardware implementation. Most of the existing AES Substitution box hardware implementation uses separate Substitution byte and its inverse hardware structures. But we implement the both in the same module and a control signal is used to select the substitution byte for encryption operation and its inverse for the decryption operation. By comparing the gate utilization of the previous AES S–Box implementation, we reduced the gate utilization up to 5% that is we take only 78 EX-OR gates and 36 AND gates for implementing the both Substitution byte and its inverse. While implementing an AES algorithm in circuitry or programming, it is liable to be detected by hackers using any one of the side channel attacks. Data to be added with a random bit sequence to prevent from the above mentioned side channel attacks.