Securing transmissions is crucial for ensuring the confidentiality, integrity, and validity of information as it moves from one point to another. Thus, a secure cryptographic system is essential to protect the data. This paper proposes the design and implementation of a secure serial communication utilizing symmetric cryptography to achieve the objectives of security, maintainability, and reliability. The Advanced Encryption Standard (AES) algorithm is used to encrypt the 128-bit plain text with a fixed key, and decryption is carried out via UART. The ciphertext is stored in hexadecimal format to offer further protection against brute force attacks and illegal data access. When compared to the current security-based application system's conventional UART serial connection, using AES as an application would be a viable option for significant improve in security. Implementation of AES algorithm on VIVADO 2020.2 and presentation of the final display on TERA TERM tool are described. BASYS 3 FPGA device is used for hardware evaluation with Verilog HDL programming. The simulation results verify the effective-ness of the algorithm.