The deal is the biggest for any football club, the Spanish champions said on their website, and will net the Catalans, the second-richest club by income behind arch rivals Real Madrid, as much as 170 million euros.
The total includes 15 million euros for commercial rights for the current season and a bonus for winning titles that could be as much as 5 million, Barca added.
"With this accord, Barca becomes the undisputed brand leader in world football, far ahead of international rivals," Javier Faus, a club vice president, told a news conference.
He added that the fresh injection of cash would help strengthen sporting projects, though he cautioned that the heavily-indebted club's financial situation remained delicate.
"Less so, but still delicate and the austerity plan led by the director general will be carried forward 100 percent," he said.
The Qatar Foundation, founded by Sheikh Hamad Bin Khalifa Al Thani, the Emir of Qatar, in 1995, has projects focusing on education, scientific research and community development. It is also engaged in several corporate joint ventures.
HIGHER PROFILE
"It's a non-commercial brand, it's a foundation and an NGO (non-governmental organisation) from a small country, at once progressive and traditional, which aims to raise its profile in the world through education and sport," added Faus.
Last week the tiny Gulf state was chosen by football's governing body FIFA to host the World Cup in 2022, when it will become the first Arab country to stage the finals, and Barca coach Pep Guardiola was one of the ambassadors for the bid.
The club are one of the few in world football not to have a corporate logo on their first-team shirts, instead displaying the name of the United Nations Children's Fund, UNICEF, for which they pay the organisation 1.5 million euros a year.
Under the agreement announced on Friday, marketing experts will seek to find a way for both logos to be displayed, although if that was not possible the UNICEF name could be moved to another part of the shirt, with priority given to the Qatar Foundation logo, a club spokesman said.
The agreement also includes a commitment for Barca to play one friendly per season, not necessarily in Qatar, and the Qatar Foundation will take part in joint projects with UNICEF and the club's own foundation.
A study by consulting firm Sport+Markt published in October showed new deals for English Premier League clubs Manchester United and Liverpool, with insurance brokerage AON and bank Standard Chartered respectively, were the two most valuable contracts in 2010/11 at 23.6 million euros each.
Real Madrid's 23-million-euro deal with Internet bookmaker bwin was the next biggest.
