The couple got married in the morning at a resort hotel.
While the 30-year-old Ghajini actress donned a white gown, the groom opted for a black suit and bow tie.
Gracing the occasion was Asin-Rahul's close friend and superstar Akshay Kumar, who also played cupid for the couple.
He shared a picture on Twitter and wrote,"Wishing d Happy Couple,Asin & Rahul a lifetime of Love & Adventures, indeed made 4 each other. Love & prayers always."
"It was a beautiful wedding. Everyone looked amazing. Akshay was present. It was Asin's idea to have a Catholic wedding. We all are very happy," said a close relative of Rahul.
Delhi-based music group Elohim Worship band performed at the wedding.
"Everything went great at the wedding. We played some 2-3 songs. Asin looked beautiful in her white gown. We had a rehearsal yesterday," said a band member.
The wedding rituals began around 11 and went on for about 30 minutes.
The couple had a second ceremony as per Hindu rituals in the evening at the same venue.
"The time for the wedding was 7 pm and it included jaimala and pheras," said one of the priests invited to solemnise the marriage. Around 200 people had been invited by Rahul for the evening ceremony, sources said.
A big reception will be held in Mumbai on January 23.
Why every family should take their children for Airlift
When Irrfan wanted to be killed off
Who does the Shah Rukh Khan pose best? VOTE!
PIX: Divyanka Tripathi gets engaged to Vivek Dahiya
Salman Khan trains hard for Sultan