Professor Alan Sked told Euronews the party is a 'joke' and is going into a 'suicidal fit', after current leader Henry Bolton refused to step down.
UKIP must "reform or die" Nigel Farage has said.
Insisting its future hinges on a crunch vote next month, the former leader warned the anti-EU party could be "worthless" in 18 months time without major structural change.
The comments by Farage come amid a crisis over the leadership of current UKIP head, Henry Bolton and allegations over his private life.
Farage has suggested Bolton may still be able to ride out the storm, but Professor Alan Sked, the man who founded UKIP, has told Euronews that the current leader has made the party a laughing stock and it is now time for it to disappear.
'It seems to be going into a suicidal fit at the moment," Sked said.
Bolton's ex-girlfriend has been accused of sending racist text messages about Prince Harry's fiancee Meghan Markle.
Despite a wave of senior resignations over the handling of his personal relationship, Bolton has refused to quit insisting he intends to ''drain the swamp".
Some fear if UKIP does fold there will be no one to hold the government to account over Brexit, but Sked believes the party has lost all political credibility.