Thiruvanchikulam Mahadeva Temple, Ancient Hindu temple in Thrissur district, India.

The Thiruvanchikulam Mahadeva Temple is a Hindu temple in Kerala featuring characteristic sloped roofs, stone walls, and intricate carved details typical of the region's traditional style. The structure showcases the architectural craftsmanship of its period, with carved elements visible throughout the complex.

The temple is believed to have been built during the Chera period; before that it was a small shrine. Mahodayapuram, capital of the Kulasekharas, grew around it. Tipu Sultan's troops damaged it and looted the copper roofing, gold and jewels; Paliath Achan of the Paliam family rebuilt it. In 1780 the Dutch attacked it, and in 1801 the Cochin government restored it and reinstalled the image brought from Chidambaram. It became a protected monument in 1982.

The daily Palliyara Puja, held after the doors close at night, is performed in only two Kerala temples; childless couples and the unmarried vow to it here. On full-moon and Monday nights it draws the most devotees. The temple keeps images of Sundara Murthi Nayanar and Cheraman Perumal, brought out during the Swati festival in July–August.

The temple lies in the middle of Thiruvanchikulam village, about two kilometres south of Kodungallur town. The west gopuram, damaged in Tipu Sultan's campaign, still stands in its broken state. The sanctum is reached through a flagstaff aligned with the entrance tower; two temple tanks sit in the second precinct. The site is a protected monument under the Archaeological Survey of India, so any renovation needs its permission.

The temple is the only Kerala shrine in the Tamil Saiva canon, the Tevaram, and the only one in the state with images of the Saiva saints installed. Figures of Sundara Murthi Nayanar and Cheraman Perumal are kept at the Bhagavathi temple and brought here for the Svati festival in July–August.