The social media platform received backlash after a photograph of two men locking lips was taken down from photographer Stella Asia Consonni's account for "violating community guidelines".
But now, Instagram have issued an apology, and have claimed the photo - which was taken for i-D magazine - was removed by mistake.
A spokesperson for Instagram said in a statement: "This post was removed in error and we are sorry. It has since been reinstated."
London based photographer Stella had posted the photo of Jordan Bowen and Luca Lucifer on Saturday (30.06.18), and revealed she had been receiving homophobic messages.
She told Newsbeat: "I am receiving many hate messages, saying that it's disgusting and that I should kill myself for posting that."
The photo reappeared on Stella's Instagram feed the following day, after high profile users of the site including Years & Years frontman Olly Alexander and Little Mix star Jade Thirlwall slammed the removal of the image.
On his Instagram story, Olly wrote: "just been informed @instagram removed the following image for being 'offensive and against guidelines'..... Let's take a look!
"ummmmmm!!??? Please can you provide a response @instagram
"Not offensive (sic)"
Meanwhile, Jade wrote: "How is this image 'offensive and against guidelines'
"Would this be the same for a heterosexual couple kissing? (sic)"
Jordan also responded to the photo being deleted, saying his seven-year relationship with Luca had been "reduced to a community guideline."
Instagram says the photo is among the "millions of reports a week" they receive from offended users and that it should not have been removed.