Google has announced a €150m extension to its second data centre in Grange Castle in West Dublin.
The move will bring to €1bn the amount of money invested by the company in Ireland since 2003.
400 temporary construction jobs will be created during the building of the facility.
It will take 16 months to fully construct and commission the expanded centre.
Around 40 permanent roles will be created once it is up and running.
Research commissioned by the company has found that between 2011 and 2017 Google's data centres here have added €350m to the economy through construction and operations and €400m to GDP
4,900 jobs are also directly and indirectly supported by the centres.
Google employs over 7,000 people in Ireland.
The announcement had been welcomed by the Minister for Business Heather Humphreys.
Google's data centres here provide the infrastructure to keep cloud-based services such as Gmail, Maps, and YouTube running efficiently across Europe, Middle East and Africa.
The second facility was announced in 2015 and opened a year later.
"This investment shows our continued commitment to Ireland as a key driver for the whole EMEA region, and we're proud to see that total capital investment by Google in Ireland has reached a total of €1 billion since we first opened an office here in Dublin fifteen years ago," said Terence McGoff, Engineering Director at Google.
Google's EU Regional Data Centre Lead Denis Browne said "Dublin is a key site in our family of European data centres, which provide the critical infrastructure to keep cloud-based services such as Gmail, Maps, and YouTube running efficiently across Europe, Middle East and Africa."
Google says its Irish data centres are designed to be highly energy-efficient, with the data centre here in Dublin using advanced air-cooling technologies, taking advantage of the country's temperate climate to regulate the temperature of the servers.
Minister for Business, Enterprise and Innovation Heather Humphreys said today's announcement is "a testament to Google's ongoing commitment to Ireland as a key hub for its operations.
"This €150m data centre expansion brings the company's total investment in its Irish data centres alone to €500m, and its capital expenditure to almost €1bn.
"There is no denying that this is a considerable vote of confidence in Ireland as a place to do business."