Facebook is building a network for professionals to connect and collaborate on work-related documents, the Financial Times reports.
Facebook at Work will look similar to its existing social network, but users will be able to keep their personal profiles separate, the paper says.
They also would be able to chat with colleagues, build professional networks and share documents, people said to be working on it told the Financial Times.
Facebook has been contacted by the BBC.
A spokesman said the company would respond later today.
The product, said to be in use internally at Facebook already, could be a strong competitor to existing services such as Google Drive, Microsoft Office and LinkedIn.
LinkedIn, which launched in 2003, is currently the largest professional network, with 332 million users in more than 200 countries, according to its website.
Facebook recorded 1.35 billion monthly active users in September 2014 - but some employers remain sceptical about the usefulness of social media at work, and many have banned it in the office.
"Facebook at Work is likely to bring some benefits to companies - but not the ones they think," said Prof Andre Spicer, of Cass Business School.
"It is unlikely to make employees more productive, but it will help them to be more connected and aware.
"Social media sites like Facebook help employees to build 'weak ties'.
"These are people we would talk to infrequently and don't know intimately.
"These weak ties are often a source of important background information."
Prof Spicer added that the new tool could also cause problems.
"It makes it easier for employees to accidentally leak sensitive information.
"It can also be a threat to hierarchy and clash with implicit or explicit chains of command."
Like its parent site, Facebook at Work could also end up being a time-consuming distraction, he warned.
"Communication which could easily be dealt with face to face is pushed online - adding another potential source of information overload," he said.
"It can also mean employees spend more time polishing their Facebook profile than actually working."