Ettumanoor Mahadeva Temple is a famous Hindu temple located in the town of Ettumanoor in the Kottayam district of the Indian state of Kerala. It is dedicated to Lord Shiva and is considered one of the most ancient and prominent Shiva temples in Kerala.

The temple's main deity is Lord Shiva, worshipped in the form of a self-manifested Shivlinga (lingam) known as "Ettumanoorappan." The term "Ettumanoorappan" means "the Lord of Ettumanoor." The lingam is believed to have been consecrated by Lord Parasurama, the mythical creator of Kerala.

The temple architecture follows the traditional Kerala style, with a gopuram (tower) at the entrance and a rectangular sanctum sanctorum. The temple also features intricate wood carvings and mural paintings depicting various mythological scenes.