Thiruvidaimarudur (also spelt as Thiruvidaimaradur or Tiruvidaimarudur) is a panchayat town in Thanjavur district, in the Indian state of Tamil Nadu.

Located about 9 km (5.6 mi) north-east of the temple city of Kumbakonam and serves as one of the Taluk headquarters in the Tanjore District.

There is also a separate sanctum (sannidhi) for Mookambikai (in Tamil, மூகாம்பிகை, mūkāmbikai) with a Maha Meru (in Sanskrit, mahāmeru, meaning "great sacred mountain").

Other significant festivals include the 63 Nayanmar Ula (in Tamil, நாயன்மார் உலா, a procession honouring the 63 Shaivite saints) and Arudra Darisanam (ārdrā darśana, meaning "sacred sight of Lord Shiva on the Ārdra star day"), similar to the celebration in Chidambaram.

Tiruvidaimarudur is the birthplace of the Hindu Saint Pattinathar - in the medieval period - whose lyrics are renowned for realizing self in the Tamil Saiva tradition of Hinduism.