The social media giant has signed a deal with British Land that will see it add 66,000 sq ft to its existing 87,000 sq ft office to the Regent's Place development, situated at the northern fringe of Central London.
The expansion comes after Facebook withdrew from its 36,000 sq ft office in Covent Garden - a space now occupied by Candy Crush creators King Digital.
Facebook is one of several Silicon Valley tech giants paying attention to the area north of the Euston Road, which is in the midst of a multibillion redevelopment.
Google is building a giant campus approximately one mile to the east in King's Cross that will be able to accommodate thousands of Googlers, while Twitter was also due to move in next-door to Facebook at one stage.
Other organisations in the area, which has been dubbed the Knowledge Quarter, include UCL, the Guardian and the government's Digital Catapult Centre, which is located above the Techworld office.
James Danby, head of office leasing at British Land, said: "Facebook's decision to expand their presence at Regent's Place is a fantastic endorsement of the campus, and underlines their commitment to this location.
"While the area's connectivity and the quality of the office space are of course significant factors, our work to make Regent's Place a vibrant destination in its own right has been crucial in attracting high calibre media and technology businesses, of which Facebook is unquestionably one."
Facebook will occupy the fifth floor of the building, as well as floors nine to sixteen and a ground floor events space, totalling 66,000 sq ft in the property at 338 Euston Road. This space is in addition to the 87,000 sq ft that Facebook already occupies at 10 Brock Street, Regent's Place.