Thrikkunnapuzha is the north-west part of Alappuzha district. Renowned as Sreemoolavasam, this coastal area found in the kerala history. An ancient port city and a busy port is believed to have been flourishing there in the ancient days. Some ancient manuscript reveals that this port city situated 5-6Kms away from the present Sastha Templewhich is now eroded by the sea. Well known historian Sree Ilamkulam Kunjan Pillai in his famous book ‘keralolpathi’ describead about this place. The Chinese explorer Huan Sang gives a note that, among the inhabitants here the ‘Pali aryas’ were dominant and they established a monastery with holy idles of SreeBudha. The ancient Sreemoola vasa nagaram was destroyed by the huge tidal waves from the Arabian Sea.

Yet another story is in vogue about the existence of the old city. Parasurama the sixth incarnation of lord Mahavishnu, as he ventured to take vengeance against all the kshatriyas here was not fortunate enough to keep away from the anger of Parasurama. He killed them one by one and invaded their domains. Later he decided to divide the place in to 64 parts and give it to Brahmins. One among the 64 part was Sreemoolavasam or Sreemoolapadam. As his mind filled with sorrow that he had killed thousands of innocent people he decided to confess. He setup 64 temples and placed it with idles of Lord Siva, Lord Vishnu, and Lord Sasthav. After centuries the temple were eroded by the tidal waves. As the sea receded the idle of Sastha and debris of the temple were recovered and was believed to have been kept by the residents.

Hundreds of years ago Keralam had been ruled by the emperor ‘Cheraman Perumal’. He established places at Thrikkakkara, Kodungallur, and Kollam for administrative purpose, and deputed his representatives there. As he was an ardent follower of Lord Budha he decided to divide the dynasty among his sons and went for a holy journey. As he was traveling with his servants and budha monks through Ashtamudi kayal and Kayamkulam kayal he happened to see a river flowing to north. He continued to travel through the river. As he traveled more he reached a place were he happened to see a beautiful lawn and in the middle of which a big Thiru Konna (a tree blooming only in the vishu ) He stopped his boat and decided to take rest there. People in large number crowded there to see Perumal and tell there grievance. The brought to notice, the Sastha idle which they got from sea and the debris of the ancient temple. Acknowledging their request Perumal build a new temple and sanctified the idle of Sastha there. ‘Thirukkonna puzha’ called by Perumal was unified to ‘Thrikkunnapuzha’ as year passed, and the temple was renowed as ‘Thrikkunnapuzha Sri Dharma Sastha Temple’. It was nearly 3Km to the west of the present temple.