PostNord, the Swedish-Danish postal service, is believed to be the first company in the world to turn the flag motif into a stamp.
The firm announced on Wednesday that it wanted to promote the diversity of "modern Sweden" with the project, due for release on May 4th.
What the stamp looks like. Image: PostNord
"By issuing a stamp with the Pride flag, we want to emphasize the equal value of all people and the strength represented by people's unique qualities and differences," said Per Ljungberg, Head of Communications at PostNord Sweden, in a press release.
"To the best of our knowledge, this is the first time the Pride flag has been reproduced on a stamp – which makes it particularly gratifying that people will now be able to send affectionate greetings with the Pride Flag stamp to all corners of the world,” he added.
However PostNord said it was Lisa Rydell, the artist behind the design, who first came up with the idea during a long summer walk two years ago and was later commissioned to work on the project.
"Swedes really like to send and receive stamped letters and postcards," she said ahead of the launch.
"For many people, the choice of stamp is an extension of their written message – which will be made especially profound with the new Pride stamp."
Sweden already has a reputation as one of the world's most tolerant nations when it comes to sexuality.
In 2014 campaign group ILGA-Europe rated Sweden the top spot in Scandinavia for lesbian, gay, bisexual, transgender and intersex people (LGBTQ). Last year Sweden set new record for Pride events with more than 30 Swedish towns and cities organizing special celebrations in 2015.
The Pride flag was first launched during San Francisco's Pride festival in 1978. Created by artist and activist Gilbert Baker it's colours are meant to suggest a range of symbolic links, for example green refers to nature while orange represents healing and violet emphasizes spirituality.