The London-based group has secured the 10,000 sq.ft former Maddison nightclub in the Welsh capital.
Opening in September, the bar will take on 65 new staff and serve a bespoke range of cocktails, 'dirty' burgers and hotdogs.
A spokesperson said the move was the ‘first stage of national expansion’ for the fast-growing brand, which served over half a million martinis during happy hour in 2015.
Scott Matthews, chief executive officer at Dirty Martini, said: “This is a big step for us and Cardiff’s strong economic growth and outstanding nightlife offers the brand a fantastic opportunity to establish Dirty Martini amongst a city of discerning cocktail lovers.
“It’s one of the best nights out in the country and we look forward to bringing Dirty Martini to the Welsh capital.”
Dirty Martini began in a Covent Garden basement and has since grown to a seven-strong group with budgeted sales of £12.5m in 2016.
The bar group currently operates seven other sites across London in Bishopsgate, Clapham, Covent Garden, Hanover Square, Islington, Monument and St Paul’s.