Mugaiyur is a block in Viluppuram District of Tamil Nadu. Located on the Viluppuram-Tirukkoyilur State Highway, this administrative unit is about 19 km west of Viluppuram and 13 km from Tirukkoyilur. St Francis Xavier’s Church is a landmark here.
Thiruvennainallur, known for an ancient Shiva temple, is 14 km from Mugaiyur. Odiyattur, Sithalingamadam (or Sittilingamadam) and Kanai are the nearby places.