The Mistry family, the Weston family and John Gyaken have taken the top three spots in the 2018 Sunday Independent Rich List.
New entrants this year include Conor Mc Gregor and entrepreneur Tommy Kelly of eShopworld.
They are worth €140m and €150m respectively.
The list estimates wealth based on stock market filings, documents in the companies registration office, annual reports and information disclosed in interviews.
The top 10 entrants increased their fortunes by over €2bn over the past year.
The 10 wealthiest have a collective estimated worth of more than €50bn, compared with €47.9bn in 2017.
#1 €15.6bn The vast wealth of Pallonji Mistry and his family comes from his stake in Tata, the largest private conglomerate in India.
Mistry gave up his Indian passport and became an Irish citizen in 2003, on the basis of his marriage to Dublin-born Patsy Perin Dubash.
Their children, Cyrus, Shapoor, Aloo and Laila, are also citizens.
The bulk of the Mistry family wealth comes from a stake in Tata Sons - the holding company for the Tata group which owns interests ranging from Jaguar, Land Rover and Tetley tea to vast steel works.
Hillary Weston recieves a degree of doctor of literature from UCD in 2009 | Image: James Horan/RollingNews.ie
#2 €8.1bn Dublin-born Hilary Weston is married to Galen Weston, Canada's second-richest man.
The family owns a retail empire that includes Brown Thomas and Arnotts in Ireland, the Loblaw grocery chain in Canada, and Selfridges in the UK.
#3 €5.8bn American private equity mogul John Grayken renounced his American citizenship in 1999 for tax purposes and became an Irish citizen.
He is the founder and sole owner of Dallas-based Lone Star Funds, which has raised money to buy up assets 1995.
His strategy is to buy distressed property assets in countries experiencing economic turmoil, clean them up and flip them for a huge profit.
He turned his attention to Ireland during the financial crisis.
#4 €5bn Entrepreneur Denis O'Brien's considerable assets span the telecoms and media sectors, among others.
#5 €3.5bn Animal nutrition accounts for most of the fortunes amassed by Alltech tycoon Pearse Lyons.
But he has turned his attention to whiskey of late.
He and his wife Deirdre bought and restored a 19th-century church on Dublin's James's Street to house the Pearse Lyons Distillery.
The firm also brews a number of craft beers.
Other notable entries on the list include:
#10 €1.92bn Limerick brothers John (27) and Patrick (29) Collison each own 12% of their online payment business, Stripe.
Their firm also made a deal with online shopping giant Amazon last August.
Michael O'Leary | File photo
#16 €1.15bn Michael O'Leary is the boss of Irish low-cost carrier Ryanair
#21 €845m Bono, The Edge, Larry Mullen and Adam Clayton of U2
#111 €140m Mixed martial arts fighter Conor McGregor is a new entry on the list
#114 €135m Enya, one of the most successful female musical artists in Ireland and Britain
Liam Neeson File photo
#124 €122m Actor Liam Neeson
#246 €50m Three-time Oscar winning actor Daniel Day-Lewis
#247 €50m 'James Bond' actor Pierce Brosnan
#248 €49m Live Aid organiser and activist Bob Geldof