Describing the resignation honours lists, as a "complete anachronism", the minister said: "We have not seen anything like this since Harold Wilson's lavender list and we hoped that we never live to see that again.
"I find it extraordinary - what on earth is possessing him? I have had so many complaints from constituents. Basically it is all his mates."
Katie Ghose, chief executive of the Electoral Reform Society, said Cameron's "parting gift of 16 lords is a sorry legacy, both in terms of cost to the taxpayer and the quality of our democracy".
Cameron had "packed the second chamber with former politicians, donors and party hacks" which would "cost the taxpayer millions over the long term" in expense claims.
Tim Farron, the Liberal Democrat leader, said: "David Cameron's resignation honours list is so full of cronies it would embarrass a medieval court."
The full list included aides of Cameron, donors to the party and officials who ran the failed Britain Stronger in Europe campaign ahead of the European Union referendum.
The new 16 peerages - including Shami Chakrabarti as a new Labour peer - takes the number in the House of Lords to 813, making it one of the world's biggest legislative chambers.
Among 13 new Tory peers are donors Andrew Fraser, the co-treasurer of the Tory party and Jitesh Gadhia, a former senior managing director at US private equity firm Blackstone. Andrew Cook , a former Tory treasurer and chairman of William Cook Holdings, is also made a knight. Together the three businessmen have given the party nearly£1.5 million ($2.8m).
The list of 46 other awards included knighthoods for Cabinet ministers Michael Fallon and Patrick McLoughlin and former ministers Oliver Letwin and Hugo Swire while former chancellor George Osborne becomes a Companion of Honour.
Aides receiving peerages include Liz Sugg, Cameron's head of operations, Camilla Cavendish, who ran the Number 10 policy unit, and Gabby Bertin, his head of external relations.
Charlotte Vere, who ran the failed Conservatives In campaign at the EU referendum, is also made a peer while Will Straw, the head of the Stronger In campaign, accepted a CBE despite pressure from Labour.
Notable by their absence are former Conservative treasurer Michael Spencer, whose nomination for a peerage was blocked by an independent advisory committee, and Tory donor Ian Taylor, who asked for his name to be withdrawn after negative publicity.
Tony Gallagher, another Conservative donor whose name was on a leaked list on Sunday, did not appear in the final version published by the Cabinet Office.
There were OBEs for Osborne's chief of staff Thea Rogers and her deputy Eleanor Wolfson, and an MBE for his constituency manager Jane Robertson.
Isabel Spearman, a stylist to Cameron's wife Samantha, received an OBE for political and public service.
Separately a report published by the Committee on Standards in Public Life warned that "the main parties have become dangerously reliant on mega-donors".
It warned: "There is a fear that major donors expect and are led to expect privileged access to the Government in order to promote their business interests."
It added that "the existence of a House of Lords Appointments Committee has provided a measure of assurance that those proposed for peerages are not merely being rewarded for their political contributions. But it has not resulted in the disappearance of concerns."
