Hash-based cryptosystem is most active research area in cryptography. Hash-based cryptosystem provides more security and authenticity because hash functions are irreversible or one way function, so no one can determine key of any hash-based cryptosystem. Motivation: Quantum computers, with their unprecedented processing power, have the potential to solve complex mathematical problems at speeds that could render traditional cryptography systems obsolete. This looming threat has spurred the development of post-quantum cryptography, aimed at creating algorithms resistant to attacks from quantum computers. Methodology: Hash functions have long been a fundamental building block in cryptographic systems. They transform input data into a fixed-size string of characters, making them integral to various security protocols. In the context of post-quantum cryptography, researchers are exploring new ways to harness the power of hash functions to create robust encryption schemes. In this article we discuss about research progress of Hash-based cryptosystem and propose a new hash-based crypto-algorithm which can be considered as post-quantum candidate in today’s cryptography world.