The Tesla chief executive said last year’s banning of Mr Trump was a “mistake” and a “morally bad decision”.
“Permanent bans should be extremely rare and really reserved for accounts that are bots, or scam, spam accounts … I do think it was not correct to ban Donald Trump,” Mr Musk said at a Future of the Car event hosted by the Financial Times.
“It was a morally bad decision to be clear, and foolish in the extreme. … I do think it was not correct to ban Donald Trump … I think that was a mistake … it alienated a large part of the country and did not ultimately result in Donald Trump not having a voice.
“I would reverse the permanent ban … I don’t own Twitter yet. So, this is not like a thing that will definitely happen, because what if I don’t own Twitter?"
Mr Musk's musings on Mr Trump may, however, be academic.
The former president, who has started his own social media company, said he would not return to Twitter.
“I like Elon Musk. I like him a lot. He’s an excellent individual … I was disappointed by the way I was treated by Twitter. I won’t be going back on Twitter,” he told CNBC last month.
Last month, Twitter entered a definitive agreement to be acquired by an entity wholly owned by Mr Musk, for $54.20 a share in cash.
Upon completion of the transaction, which is expected to be by the end of this year, Twitter will become a privately held company.
Eighteen investors have made commitments ranging from $850,000 to $1 billion to help Mr Musk finance this deal, a regulatory filing in the US Securities and Exchange Commission said.
The San Francisco-based microblogging site permanently suspended Mr Trump’s account in January 2021, citing “the risk of further incitement of violence” following the deadly Capitol insurrection.
The social platform was under immense pressure to take action against him after the mob attack at the US Capitol.
Twitter initially suspended Mr Trump's account for 12 hours after he posted a video that repeated unsubstantiated claims about election fraud and praised the rioters who stormed the Capitol.
At that time, he had more than 80 million followers on the public platform.
In July, Mr Trump announced filing lawsuits against Facebook (now Meta), Twitter and Google, and their chief executives. Mr Trump claimed that he has been wrongfully censored by the companies.
Mr Musk’s offer to buy Twitter came after frequent complaints about content censorship and a lack of free speech on the site.
In response to a poll he conducted on the platform, 70.4 per cent of users said Twitter did not stick to free speech principles, while 29.6 per cent supported the platform.
Following the announcement of his acquisition, Mr Musk tweeted: “I hope that even my worst critics remain on Twitter, because that is what free speech means.”