The singer was in London for a recording session when she passed away.
The cause of death has not been revealed.
A spokesperson for the star told the Limerick Leader: ‘Irish and international singer Dolores O’Riordan has died suddenly in London today.
‘She was 46 years old. The lead singer with the Irish band The Cranberries was in London for a short recording session. No further details are available at this time.’
The Cranberries were hugely successful in the 90s, selling over 40 million records worldwide.
Their most well-known hits include ‘Linger’ and ‘Zombie’.
Last year, the band were forced to cancel tour dates in Europe, the UK and the US due to O’Riordan’s health issues.
The official Cranberries website stated that the cancellation was due to problems with the singer’s back.
O’Riordan formed the band in 1989 with brothers Noel and Mike Hogan after reading an advertisement in a local paper.
She also released solo records Are You Listening? (2007) and No Baggage (2009).