Fathers working at Guinness will be entitled to 26 weeks of leave on full pay when they have a baby, matching maternity benefit already paid to women, from July 1.
The dramatic move by one of the country's biggest employers is being hailed as a potential game-changer in gender equality.
The 26 weeks of paid parental leave will be offered to all Diageo employees in Ireland who become parents, regardless of gender, sexuality, or whether they became parents through birth, adoption or surrogacy, the company announced yesterday.
Diageo hopes the policy will support employees to "focus on the joy of raising a young family, while continuing to thrive at work".
The company, whose brands include Baileys, Smirnoff, and Tanqueray gin, currently employs 1,200 people across the island of Ireland.
The news follows an announcement last month from Diageo that all its employees in the UK are eligible for the same paternal benefits.
"Our business has always had strong record of being one of the best employers in Ireland," said Diageo Ireland's country director Oliver Loomes.
"[Yesterday's] announcement is a significant step for us and shows our commitment to leading the way with progressive employment policies by supporting gender equality in the workplace."
The ambitious plan comes when the country is close to full employment, with a record 2.3 million people in work.
In the first quarter of this year, 35,200 jobs were created, most full-time and many of them going to women. Unemployment is at the lowest level in 14 years.
David Joyce, equality and international development officer at employee representative body ICTU, said Diageo's move was "a very positive development".
"Progressive companies know the research demonstrates that paternity leave saves them money by attracting and retaining employees, including women and men," Mr Joyce said.
"This will be a major contribution to tackling other gender inequalities in the workplace, including the gender pay gap."
A spokesperson for trade union Siptu said the news was "very welcome".