Speaking at Prime Minister's Questions, Cameron came under pressure from backbench Conservative MPs, as well as Labour MPs and the Scottish National Party.
John Mann, a Labour MP who sits on the Treasury Select Committee, said: "Is that it? Is that all that he can do? Nothing for pensioners or workers?"
Cameron defended the draft agreement, saying he thinks the United Kingdom will succeed more if it exists in a reformed EU.
Meanwhile, Conservative MP Christopher Chope asked the Prime Minister to confirm he had been forced to abandon the manifesto promise on banning benefits for migrants for four years. However, Cameron disagreed with him.
And the SNP's Angus Robertson pressed Cameron on whether he will give a commitment on not holding the referendum in June, which he said would clash with the Scottish parliamentary election.
Yet, the Prime Minister guaranteed the referendum will not be held within six weeks of devolved elections, as called for by for Alex Salmond.
For his part, Labour leader Jeremy Corbyn waited until Cameron's statement to respond on the EU, calling the Prime Minister's negotiation a "Tory drama that's being played out in front of us". He added that Labour wants the UK to stay in the EU, but Cameron has been negotiating the "wrong goals in the wrong way for the wrong reasons".
Cameron responded by urging all sides of the House to "fight this together".