Vishwanathan Venkatachalam was born on 7 July 1925 in Kovilpatti, Tirunelveli (now Thoothukudi) district of Tamil Nadu. His father was a Head Master and mother a homemaker. In his early years, Venkatachalam won gold medals from Madras Sanskrit College and Sriperumbudur Sanskrit College; numerous book-prizes from St. Xaviers College and Madras Sanskrit College for competitions in areas including essays, elocution, declamation, and debate in Sanskrit as well as in English; book/cash prizes from institutions like Sanskrit Academy, Kuppuswami Sastri Research Institute, Theosophical Society and Ramakrishna Math of Chennai and an All India Essay Competition in English from Ramakrishna Math, Sorisha, West Bengal.

He acquired dual Bachelor of Arts degree in Sanskrit and Mathematics from Madras University (1944). He was awarded the Sri Godayvari Sanskrit Prize by Madras University in B.A. (Sanskrit) exam. He was awarded the Pitti Muniswami Chetty Garu Gold Medal by Madras University for first rank in the Siromani exam with Advaita Vedanta as specialisation (1949). He went on to earn his Master of Arts Degree in Sanskrit (Classical Literature and Alankara as specialisations) from Nagpur University (1951). He was awarded Daji Hari Wadegaonkar Gold Medal by Nagpur University for first position in M.A. (Sanskrit) exam. Prof. Venkatachalam was a polyglot well versed in Sanskrit, Hindi, English, Tamil and Malayalam. He earned a certificate in German from Vikram University, Ujjain in 1965

Venkatachalam started his career in 1949 as a lecturer in Sanskrit at Vivekananda College, Madras. From 1954–1966 he served as Assistant Professor/Professor of Sanskrit in Madhav College, Ujjain, MP. In 1966 he was appointed Principal of Government College, Barwani (MP) and went on to be Reader and Head of Sanskrit Department at Vikram University, Ujjain, MP a year later. He was later appointed Principal of Government Post Graduate College, Shajapur, MP in 1972. He again moved to Vikram University, Ujjain, MP in 1974 to be Reader/Professor and Head of the Sanskrit Department till 1985. Concurrently he became the Director of Scindia Oriental Institute at Vikram University, Ujjain, MP. From 1986 to 1989 he was appointed vice-chancellor of Sampurnanand Sanskrit University, Varanasi, UP. After his term at Sampurnanand Sanskrit University, he was Director of Bhogilal Leherchand Institute of Idology in Delhi till 1992. He was invited to serve as the vice-chancellor of Sampurnanand Sanskrit University for a second term from 1992–1995. Concurrently he was also honorary Chancellor of Shri Lal Bahadur Shastri Sanskrit Vidyapeeth, New Delhi till 1997. From 1996–1998 he served as the vice-chancellor for Kameshwar Singh Darbhanga Sanskrit University, Darbhanga, Bihar. Concurrently, from 1997 onwards, he was the Chairman of the Indian Council of Philosophical Research, Ministry of Human Resource Development, Department of Education, Govt. of India.[2] He served in the Board of Editors on Encyclopedia of Hinduism.

He visited and gave talks in many countries including Malaysia, Singapore, Italy, France, Germany, USA, UK, Bali (Indonesia), Nepal, South Africa, Curaçao (Netherlands Antilles), Trinidad & Tobago and Canada.