In April 2010, Gordon Brown, David Cameron and Nick Clegg took part in hugely popular debates on Sky, the BBC and ITV to outline their bids for Number 10.
Dimbleby, who presented the debate on BBC One, questioned whether the televised debates will prove to be a positive introduction in the long term.
In a video message to the Broadcasting Press Guild awards in London last Friday, where the TV debates won a broadcasting innovation award, Dimbleby said that people may "come to regret" the change to Britain's political landscape, reports The Guardian.
"The debates certainly were an innovation. They will change the way electoral campaigns are conducted, not necessarily entirely for the better," he said.
"In one way they are odd because we don't have a presidential system in Britain. We have a parliamentary system. We don't elect prime ministers, we elect parliaments and MPs; we have after all got a coalition now.
"And looking back on it we introduced the debates as the three men who want to be prime minister. What are we going to do at the next election? Maybe say the two men who want to be prime minister and the one man who wants to be deputy prime minister."
Dimbleby also voiced his concerns that the debates could prevent leading politicians from taking part in other debate programmes, such as Question Time, in the future.
"I would hate it if these debates stop people taking part in the kind of thing we do on Question Time. During the campaign the party leaders come in, face the voters and make their case and face fierce criticism from them," he said.
"So as an innovation we have to be a bit cautious. It was fun to do - I was lucky to be third on, actually all I had to do was try and remember the next person to speak which wasn't always that easy.
"But that said it's a big innovation, a big change, an exciting event and I am really grateful for this prize. I just hope it's not one of those things that you could come to regret what you wish for."
However, Dimbleby's concerns were not shared by the Sky News political editor Adam Boulton, who said that the public engaged with the debates, both young and old.
"All the research shows they engage people and engage young people in the political process," he said after the awards.
"I don't think they distort the political process and I hope they are going to happen again. Obviously everyone has their own views. I think we would all like to experiment and innovate with the formats and do slightly different things. All that depends on having the confidence of the parties to do it."
The election debates were made possible last year after Sky, the BBC and ITV agreed to a detailed 76-point set of rules for how they would manage the process.
The debates proved an overriding success ratings-wise, as the first round on ITV1 gained an average audience of 9.4 million on April 15, followed by a combined audience of 4.1m for the Sky News debate on April 22 and 8.4m for BBC One's programme on April 29.
However, former Labour leader Gordon Brown later claimed that the "novelty" of the UK's first televised prime ministerial debates "clouded" the general election campaign.