|Time zone||UTC+5:30 (IST)|
As of 2001[update] India census, Vellimalai had a population of 11,758. Males constitute 50% of the population and females 50%. Vellimalai has an average literacy rate of 79%, higher than the national average of 59.5%: male literacy is 82%, and female literacy is 76%. In Vellimalai, 10% of the population is under 6 years of age.
Vellimalai is famous for the Lord Murugan Temple called as "Bala Subramaniya Swamy Koil" located atop of the hill Vellimalai. It is popularly believed that Valli was born here, and raised by a tribal king to marry with Lord Murugan in a Love marriage. Nonetheless, similar story is associated with another namesake place, Vallimalai in Vellore district and Tiruttani of Tiruvallur district in the far north of Tamil Nadu.
Lord Murugan Temple attracts lot of pilgrims from the surrounding areas. The famous festivals of the temple are "Sasti Sura Samkaram"- killing of Suran, the demon leader by Lord Bala Subramaniya Swamy and Vaikasi Visakam. From the top of the hill the major part of the green Kanya Kumari District can be viewed, which will be a mind blowing experience for nature lovers.
- "Census of India 2001: Data from the 2001 Census, including cities, villages and towns (Provisional)". Census Commission of India. Archived from the original on 16 June 2004. Retrieved 1 November 2008.