The YouTube star, 22, was removed from the jungle camp earlier this week after tweets containing racist and homophobic slurs he posted when he was younger were unearthed.
Maynard said he felt “ashamed” and apologised for the posts before agreeing with the decision to stand down from the show.
But fans have slammed the “ridiculous” move, arguing he should not be judged on comments he made as a young teenager.
A Change.org petition titled ‘Bring Jack Maynard Back to I’m a Celebrity, Get me Out of Here!’ has amassed over 500 signatures.
It reads: “Ridiculous how 22 year old Conor Maynard has been kicked out for tweets made while he was 15.”
One supporter wrote: “Its utter rubbish. Jack is my fave YouTuber, and those tweets were over 6 years ago, AND he has apologised. Not to mention the fact that Amir [Khan] has been homophobic in previous tweets.”
Another posted: “I think it's wrong to keep penalising this young lad when there are more disturbing things going on on this world at the moment.”
It comes days after the hashtag ‘Bring Back Jack’ was circulated in an attempt to persuade ITV to allow him to return to the programme as some viewers threatened to boycott the show.
In the posts, which date from between 2011 and 2013, Maynard used the n-word, hurled insults at disabled people and referred to other users as “f******”.
This Morning host Holly Willoughby also defended him saying she doesn’t “understand” why he had to be removed if he issued an apology.
“I don’t understand this,” she said. “We knew about these messages before he went in. He apologised – I don’t understand.”
Alison Hammond then reminded her that there were potentially more allegations against the star, which were yet to surface.
According to the Mirror, Maynard has allegedly come under fire for a series of messages he sent to a fan before entering the jungle.
Maynard is yet to comment on his exit from the show.
I'm A Celebrity is on ITV, tonight at 9pm