"He's never been the manager of an organization, he's never run a school system," Bloomberg told Stephanie Ruhle on MSNBC in an excerpt that aired on Wednesday, referring to Biden.
"The presidency shouldn't be a training job. You need somebody who comes in and knows how to run an organization," he added.
Bloomberg, 77, who jumped into the crowded Democratic primary field in November, also criticized his other opponents on their lack of qualifications, saying he doesn't think "any of them have the experience" to be president.
However, Bloomberg did say he would support the eventual Democratic nominee, including Senator Elizabeth Warren of Massachusetts, even though he doesn't "agree with her on a lot of things."
As for who he believes will win the Democratic nomination, he said he would "leave that to the prognosticators."
Bloomberg's full MSNBC interview is set to air on Thursday.
The New York billionaire businessman routinely touts his own experience in business, philanthropy, and politics -- especially as an executive in his role as New York mayor -- as his qualifications to be successful in the Oval Office.
Earlier this month, Bloomberg said he does not think any of the other candidates could hold their own in a head-to-head matchup against President Donald Trump.
"I watched all of the candidates, and I just thought to myself, 'Donald Trump would eat them up,'" Bloomberg told Gayle King on CBS News, as previously reported by The Inquisitr.
"Let me rephrase it. I think that I would do the best job of competing with him and beating him," he added.
Bloomberg, who has an estimated fortune of more than $50 billion, has faced strong criticism from other Democratic rivals, especially Warren and Senator Bernie Sanders of Vermont, who have accused him of trying to buy his way into the race.
Bloomberg has sunk more than $100 million into television ads since entering the race and is skipping the four early primary and caucus states to focus on a nationwide campaign -- a path not taken by any of the other top candidates in recent history.
That strategy appears to be giving the former New York City mayor a boost in the polls. In recent national polling, Bloomberg has rapidly climbed to fifth place behind Biden, Sanders, Warren and South Bend, Indiana Mayor Pete Buttigieg at 5.1 percent, according to averages compiled by RealClearPolitics. However, he has been unable to break the two percent mark in any of the early states.