Lydon, 61, better known as Johnny Rotten, claimed it was wrong to “smear” Mr Turmp as a “racist” when “there’s no evidence or proof” to back it up.
Speaking on Virgin Radio he said: “America now has a new president and whether you like him or not you have to support him or you will destroy the country.
“The attitudes that are being pulled on him are stupid and wrong. He’s got some serious money issues that deeply fascinate all of us but to be smearing him as a racist, this isn’t right, there’s no evidence or proof to that and until there is, I’ll stand up and say that I think that’s wrong.”
Lydon slammed “left-wing politics” for making it okay to throw out accusations which can be “damn upsetting” for the person on the receiving end.
“In my past I’ve had that accusation thrown at me willy nilly and it’s a damn hard one to have to listen to and endure – make sure it’s right,” Lydon said.
“It’s a terrible attitude in left-wing politics – they just feel they have the pomposity and right to just throw these accusations out without any evidence – well don’t because my world requires facts.
“For the next week and a half the rag-and-bone trade that we call the media is going to be calling me a racist, that’s the tomfoolery of it all. That’s going to be damn upsetting all over again to my grandkids, isn’t it?”
Lydon’s latest comments came a day after he backed Brexit, saying “the working class have spoken”.
He hailed Brexiteer Nigel Farage as “fantastic” and said he was keen to shake his hand as he referenced Farage’s encounter with Sir Bob Geldof on the River Thames ahead of the referendum last year.
Speaking on Good Morning Britain he said: “After that up the River Thames argument he had with Bob Geldof I wanted to shake his hand because it was silly beyond belief.
“Where do I stand on Brexit? Well, here it goes, the working class have spoke and I’m one of them and I’m with them.”