The first informal summit between both leaders was held in China's Wuhan, last year, months after the 73-day-long standoff between both armies in Doklam.
In Wuhan, PM Modi extended an invitation to Xi.
PM Modi and Xi will work towards strengthening ties
Xi and PM Modi will have free-wheeling conversations over the course of two days in Mamallapuram, a coastal town over 56 km away from Chennai.
Today, the Indian host will take the dignitary on a trip to three ancient sites of the town, namely Arjuna's Penance, Panch Rathas and the Shore Temple.
The venue for tomorrow's talks is Taj Fisherman's Cove Resort & Spa.
The Chinese President got a grand welcome
Tamil Nadu: Chinese President Xi Jinping arrives in Chennai. The second informal summit between Prime Minister Narendra Modi and President Xi will begin in Mahabalipuram today. pic.twitter.com/s17EDZxUqr
Xi was welcomed by Tamil Nadu Governor Banwarilal Purohit at the airport. Sharing spot visuals from the airport, PM Modi tweeted, "Welcome to India, President Xi Jinping!"
The two leaders will head to Mamallapuram, to discuss various topics like trade, defense, and terrorism.
Purohit along with Chief Minister Edappadi K Palaniswami and Deputy CM O Panneerselvam also welcomed PM Modi earlier today.
Small town has become the center of attention
The coastal town of Mamallapuram, where all the action will take place, has been decked up for the summit. Usually, the residents have a laidback lifestyle, but of late that has been hampered due to security arrangements.
Uncountable barricades have been put up in the area and CCTV cameras are keeping an eye on every movement.
Chinese officials also visited for a recce, earlier.
Xi and PM Modi will be allowed to talk freely
According to reports, the itinerary has been made in such a manner that both leaders are allowed to have free conversations, in absence of aides.
When PM Modi went to Wuhan, Xi gave him a personal visit to Hubei Provincial Museum.
Pictures from the first summit showed they enjoyed each other's company, and this time too both governments hope the same happens.
The meeting will have several implications: Chinese minister
"The meeting between Xi Jinping and PM Modi will also have far-reaching positive implications for regional and global development and stability," said Luo Zhaohui, the vice-foreign minister of China.
Will they will let bygones be bygones?
Separately, state-run Xinhua news agency said Xi and PM Modi will focus on improving ties keeping the past differences aside.
"The belated official announcement of Xi's visits to the country's two South Asian neighbors, only 48 hours ahead of the informal meeting, was proof that Beijing and New Delhi cherish the opportunity to improve bilateral ties through the personal chemistry between their top leaders," an editorial read.