The main religion followed is Hinduism with a small minority of people of other religions as well. One of the highlights of the town is the Killikkavu temple, dedicated to the worship of goddess Bhadrakali. There is a Pooram organised every year at the end of April (usually April 25) with several beautifully decorated elephants and the Panchavadyam. The Pooram brings great joy and happiness to the people of Manissery and on the Pooram and each household participates with great vigour. The highlight of the Pooram is the Vedikettu, or fireworks (on the night of the Pooram day), featuring earsplitting noises and everlasting echoes preceded by brilliant dazzling lights in the sky.