It is understood 150 people work at the office in Dundalk, County Louth.
eBay have not said how many staff will be impacted by the closure. It said it will begin a formal consultation with employees.
The company said the plant will close in the second quarter of 2017.
The closure comes after the decision to separate eBay and its PayPal business.
After the split, PayPal became landlords of the facility in Dundalk from which both companies have been based.
PayPal had told eBay that it intended to expand its business and asked tenants to leave so it could occupy the facility.
"We will begin a formal consultation process with our colleagues in Dundalk and will share any further information with them as a matter of priority," eBay said in a statement.
A spokesperson for PayPal said it was committed to its offices in Dundalk and Dublin.
"Today PayPal employs more than 2,600 teammates across both sites, and we're on track to reach 3,000 by 2018. The commitment is in line with our previous jobs announcements.
"Our operations will expand and move into the office space vacated by eBay."
Internet auction site eBay has told staff at an office in the Republic of Ireland that the facility will close next year.