The Soundararajaperumal Temple in Nagapattinam, Tamil Nadu, is a revered shrine dedicated to the Hindu god Vishnu, crafted in Dravidian architectural style. Glorified in the Nalayira Divya Prabandham, the medieval Tamil canon of Alvar saints (6th–9th centuries CE), it is recognized among the 108 Divya Desams dedicated to Vishnu, who is worshiped here as Soundararaja Perumal, alongside his consort Lakshmi as Soundaravalli.
Believed to have been built by the Medieval Cholas in the late 8th century CE, the temple saw additions from the Thanjavur Nayaks. Two Chola-era inscriptions remain on the temple premises. Its five-tiered rajagopuram (gateway tower) rises within a granite wall, surrounding the temple complex that houses multiple shrines and sacred water bodies central to worship and temple rituals.
Soundararaja Perumal is said to have appeared before Sage Markandeya, Dhruva, Saleesan, and the goddess Bhudevi. Six daily rituals and three annual festivals are observed, with the grand chariot festival during Tamil month Chittirai (March–April) being the most prominent. The Hindu Religious and Endowment Board of Tamil Nadu oversees the temple’s administration and maintenance.
A distributary of the river Kaveri, called Odambokki or Virutha Kaveri, flows near the temple. The area, once a forest named Sundararinyam, inspired devotion across ages. Legends tell of Dhruva’s penance to see Vishnu, and the appearance of Vishnu during Satya Yuga, earning him the name "Soundara Rajan." The temple's association with Nagas gave Nagapattinam its name, "place of the Nagas.