He is in the country to oversee tsunami relief work and follow up on the anti-AIDS campaign.
This is his fourth visit in five years; he first came to India as president in March 2000.
President George W Bush appointed Clinton and former president George H W Bush, his father, as his special envoys to oversee tsunami relief worldwide.
Clinton -- he had heart surgery last year, hence the slimmed down look -- will travel to Chennai on Friday morning and onwards to Nagapattinam, 400 km south, by helicopter to oversee relief and rehabilitation work undertaken by the William J Clinton Foundation.
Accompanying him on the journey is New York hotelier Sant Singh Chatwal.
Clinton will meet Prime Minister Dr Manmohan Singh and NGOs and anti-AIDS activists. He will attend a dinner in his honour hosted by Agriculture Minister Sharad Pawar on Wednesday and will have a private meal at the Bukhara restaurant, famed for its Mughlai cuisine, on Thursday.
After his Tamil Nadu visit, Clinton will travel to other tsunami-hit nations like Sri Lanka.
Photograph: Sondeep Shankar/Saab Pictures