Since December, the commission has been examining whether funding for the Â£16bn plant, to be built by developers EDF Energy, broke state aid rules.
Hinkley Point C would be the first new nuclear power station to be built in Britain since 1995.
Anti-nuclear campaigners have called the commission's decision a "U-turn".
Antoine Colombani, commission spokesman for competition and for vice-president Joaquin Almunia, said: "Our discussions with the UK authorities have led to an agreement.
"On this basis, vice-president Almunia will propose to the college of commissioners to take a positive decision in this case. In principle a decision should be taken within this mandate."
A spokesman for EDF said the recommendation was "another positive step forward for this vital project".
"Hinkley Point C is an important project which will deliver Europe-wide objectives, offering the prospect of reliable, secure and low-carbon electricity for many decades to come as well as boosting jobs and skills."
Andrea Carta from Greenpeace said: "If competition commissioner Almunia has backed state aid for Hinkley, it risks a backroom deal prevailing over the rule of law.
"Only a year ago the Commission said that Hinkley was 'in principle incompatible under EU state aid rules'.
"Now, under pressure from the UK government and French nuclear operator EDF, the commission is preparing to perform a U-turn.
"European commissioners should oppose the plan and resist rushing through a controversial and far-reaching decision in the dying weeks of this commission."
Gary Smith of the GMB union said: "We lobbied the commission to move ahead on this important project for the UK economy, so we are very pleased at this latest development and look forward to the recommendation being accepted."
The recommendation must now be approved by the commission's College of Commissioners in the next few weeks.
A final decision is expected in October.

Mr Houchen beat Labour's Sue Jeffrey by a little over 2,000 votes after second preference votes were counted. Liberal Democrat Chris Foote Wood was third and UKIP's John Tennant finished last.
Mr Houchen will have a budget of Â£15m a year.
In another result, Labour retained control of Durham County Council despite losing 20 seats.
The party won 94 seats in the 2013 election and that has now fallen to 74. Independent candidates have the second highest number of seats (28) followed by Liberal Democrats (14) and Conservatives (10).
Council leader Simon Henig said he was "very pleased" to have retained a majority in a "challenging" election.
As Tees Valley mayor, Mr Houchen will head the Tees Valley Combined Authority, made up of Darlington, Hartlepool, Redcar and Cleveland, Middlesbrough and Stockton councils.
After the declaration at Thornaby Pavilion, Mr Houchen said: "What we have seen in recent years is fantastic trends towards the Conservatives across the Tees Valley and today is, I believe, a tipping point.
"We have seen a political earthquake that's happening right here for the Conservatives across the North East.
"It's the first time anybody would expect a Conservative mayor for the Tees Valley and it is the start of five genuine target seats for the Conservatives in the upcoming general election, and I genuinely believe this is a starting point for turning the Tees Valley blue."
This is a sensational vote for the Conservatives.
Beating Labour in the first round, we perhaps thought Labour might claw it back with second preference votes. They were counted then but actually Conservatives pulled further ahead and Ben Houchen beat Sue Jeffrey the Labour candidate in a runoff to become the Tees Valley mayor.
He has now got to deliver on certain promises, one of which is to take control of Durham Tees Valley Airport and try to revive its fortunes.
He talked about turning the Tees Valley blue in the general election in just over a month's time and that will be the Conservative focus now.
Plans to build a new nuclear power plant at Hinkley Point in Somerset have been recommended for approval following a European Commission investigation.
[NEXT_CONCEPT]
Conservative Ben Houchen has become the inaugural Tees Valley mayor after winning a tightly-fought contest.