Raghunathan is a South Asian surname and patronymic. It is also variously spelled as Ragunathan. People with the name include:
K. Raghunathan (born 1957), journalist and writer from India Madabusi Santanam Raghunathan FRS (born 1941), mathematician from India Mahaveer Raghunathan (born 1998), racecar driver from India Medha Raghunathan (born 1981), model and VJ from India
Sudha Ragunathan (born 1957; née Venkatraman), Carnatic musician from India
T. M. Chidambara Ragunathan (1923–2001), journalist and writer from India Viswanathan Raghunathan (born 1954), businessman, writer, academic, from India
See also Appiah Balakrishnan, alias Ragunathan (died 1993), Sri Lankan assassin of Lalith Athulathmudali Ragunathan Rajkumar (born 1963), American computer engineering academic from India Raghunathan Srianand (born 1969), astronomer from India Raghunatha, a given name Raghunath (disambiguation)