About 70,000 people are expected to attend the day-long London Mela.
The festivities at Gunnersbury Park in west London will showcase the best of British Asian art and culture.
There are eight "zones of activities" spread over the 30 acres of land. These will include music, theatre, fashion and an area for children and families.
There is also the chance for people to take part in a mass participation Bollywood dance event.
The Mela, which is in its seventh year, is being supported by the mayor of London.
The event began at 1300 BST.