The Queensland Police Service (QPS) has denied the release of a video promoting their LGBTI officers is its way of promoting same-sex marriage.

The 10-minute video, titled It Gets Better, features male and female officers discussing their sexuality, their own experiences of coming out, and what it's like being an LGBTI person in the police service.

The video debuted at today's Wear It Purple event in Queen's Park in Brisbane's CBD, celebrating diversity, inclusion and awareness.

A shorter version was posted on the QPS's Facebook page, where it has been watched more than 57,000 times.

Senior Constable Ben Bjarnesen from Fortitude Valley station said the video project had been in the works for 12 months and was not connected to the current campaign around same-sex marriage.

Senior Constable Ben Bjarnesen shared his story in the video. ( ABC News: Meghna Bali )

"That definitely wasn't our intention. Our intention was for the project to let children know we're here to help if they need it, and to be proud of who they are," Senior Constable Bjarnesen said.

"We've launched it in conjunction with Wear it Purple day, which is about promoting good mental health among LGBTI youth and urging them to reach out if they need help."

He said they also wanted to raise awareness of the LGBTI liaison program in the QPS, the first organisation to embrace the international It Gets Better campaign.

"Like all of the officers, everyone's had their own struggles, and we just wanted to show we've all been through the same struggles and are living proof it does get better," Senior Constable Bjarnesen said.

"The liaison program reduces the gap between the police and the LGBTI community, and previously relationships between police and the LGBTI community haven't been so great, historically.

"So we're trying to close that gap and build some really good relationships with the community, and make people feel safe about reporting any crimes or matters that need police attention."

'Being gay doesn't make a difference to the job we do'

In the video, Senior Constable Bjarnesen revealed that at school he felt like he really did not fit.

He said when he joined the police service in 2007, he had a "pre-conceived" idea about what the response might be to him, but he has never had an issue.

"By doing things like the It's Get Better video, we're making a visual statement to people it is OK to be gay in the police force," Senior Constable Bjarnesen said.

"Although it's been a non-issue, people weren't aware that it was a non-issue and were still scared."

Police officers joined in at the Wear It Purple Day event in Brisbane's CBD. ( ABC News: Meghna Bali )

Among those who appear on the video is Detective Senior Sergeant Sasha Finney, who is the officer in charge of the Illicit Laboratory Investigation Team.

"Just because we're gay, that doesn't make a difference to the job we do. We're police and we do a job, and we try to do it to the best of our ability," Detective Senior Sergeant Finney said.

'You have the right to be proud of who you are'

Wear It Purple Day board member Brock Galway said her group was grateful for the support of the QPS at the festival in Queen's Park.

"There's a lot going on in society today and it's important to let LGBTI youth know that they have the right to be proud of who they are," Mr Galway said.

"Something as simple as wearing the colour purple on a day like today really reaches out to these people, and if they see you walking down the street in purple they can know and feel accepted."

Community development coordinator at National Youth Mental Health Foundation headspace, Sian Finn, said it was quite a difficult time in the community right now for young people.

Mr Galway has been on the board for Wear It Purple Day since late 2016. ( ABC News: Meghna Bali )

"We want to make sure the marginalised groups within the LGBTI community are represented, and particular trans young people in the indigenous community," Ms Finn said.

"When you talk about breaking down barriers it has to be more than tokenistic and the police being here and participating in activities just shows how committed the are to helping LGBTI youth across the board."