The 'Super Duper Love' hitmaker claimed she was "detained" before immigration officials before being removed from the country after being "blacklisted" over a fear she might perform a public show, which is illegal for females to do solo in the country.
She shared a video on Instagram, in which she wore a white headscarf and said: "Well, we got to Iran, we got detained and then we got deported."
The 32-year-old star - who is in the middle of her 'Total World Tour', where she aims to play in every country across the globe - insisted she didn't intend to play a public concert in the Islamic Republic.
She wrote: "So , our very last country on the list was Iran.
"We were aware there couldn't be a public concert as I am a woman and that is illegal in this country. Personally I don't fancy going to an Iranian prison nor am I trying to change the politics of the countries I visit nor do I wish to put other people in danger.
"However, it seems the authority's don't believe we wouldn't be playing a public show so they have popped us on what they call the 'black list ' as we found out when we turned up to the immigration hall. After long discussions with the most friendly charming and welcoming immigration people the decision was made to detain us for the night and to deport us in the morning. Of course I was gutted. So close yet so far, this moment broke a little piece of my heart.(sic)"
Joss explained she was trying to showcase the "positives of our globe" and praised the "nice, kind" officials who dealt with her and her team when they flew into Iran.
She continued: "Then I realised the silver lining was bright.
"I told them my story and explained my mission, to bring good feeling with what I have to give and show those who want to look, the positives of our globe. All with the understanding that public performance wasn't an option in this scenario.
"I still have to walk forward towards that goal some way some how. And of course music is my driver. Doesn't mean we have to brake any laws though. There is music everywhere. Even here, we just have to play by there rules and they have to believe we will. It's a trust thing.
"They were so kind to us, at one point I started to question it. The question whirled around my head, were they just luring is into a false sense of security so we would walk into our jail cells quietly with out a drama?
"Nope , these people are genuinely nice kind people that felt bad that they couldn't over ride the system.
"They didn't speak English so well so the translator Mohamed, who clearly had a lovely soul conveyed the message that they hoped we would go to embassy to sort it all out and come back, they were refusing us entry with a heavy heart and were so sorry.
"After Mo had left, the officers kept telling us sorry. They said sorry all the way through this process and kept saying this till we got on the plane they were sending us away on. We were the ones that should have been apologising for not having our correct paper work.(sic)"