Raja Mannargudi Mahamahopadhyaya Thyagaraja Mahi Raju Sastrigal (28 May 1815 – 4 March 1903), also known as Mannargudi Raju Sastri or Mannargudi Periyaval, was a Hindu scholar.
He was born in the Bharadwaja Vamsa, as a descendant of Adayappaalam Sri Appayya Dikshitar. Raju Sastri was born in the village of Kuthambadi in today’s Thiruvarur district as son of Maragathavalli Janakiammal and Sri Markasahaya Appa Dikshitar