The Guinness Storehouse welcomed almost 1.5 million visitors through its doors last year, making it the most popular fee-paying tourist attraction in Ireland, according to Fáilte Ireland.
The tourism body marked an increase of 18% in visitors to the Guinness Storehouse, in comparison with the previous year.
The Cliffs of Moher Visitor Experience was ranked as the second most popular destination for tourists with over 1.2 million people visiting last year, an increase of 16% since 2014.
Dublin Zoo was ranked in third place with over 1.1 million visitors last year, a 2.6% increase.
The National Gallery of Ireland was rated the most popular free attraction with an estimated 718,637 people visiting in 2015 (up 21% since 2014).
The National Botanic Gardens was ranked as the second most popular free attraction with 553,348 visitors - a slight increase of 2% since 2014.
The Irish Museum of Modern Art was the third most popular spot with 485,702 people visiting in 2015 - a substantial increase of 58% since 2014.
Commenting on Fáilte Ireland's rankings, Minister of State for Tourism and Sport Patrick O'Donovan said the variety of visitor attractions in across the country "plays a significant part in adding to the positive experiences enjoyed by tourists when in Ireland".
"The Government has committed significant investment over the last few years to develop both new and existing attractions, and these figures published today highlight how such investment can return dividends" he added.