Activist Predrag Azdejkovic told this to Radio Free Europe' Facebook page dubbed "Zasto."
He expects the prime minister to implement the action plan for the Strategy for Reduction of Discrimination, which was previously adopted by the government.
"It is defined there that Serbia must legally regulate same-sex partnerships, and the way in which trans persons will obtain new documents," said Azdejkovic, adding that this was "promised to the LGBT community - but nothing has been done."
"I hope the government of Ana Brnabic will implement this action plan," said the president of the Belgrade-based Gay Info Center.
The appointment of Brnabic - who is openly lesbian - also contributes to the visibility of the local LGBT community, said Azdejkovic, who "doubts there is a person in Serbia now who does not know about Brnabic, and that she is a member of the LGBT population."
"I think this will over time contribute to reducing prejudices against the LGBT population," he said.
Azdejkovic added that although he does not have "excessive expectations" from her, he sees Brnabic as "a means of activist struggle, because LGBT activists can, for example, say at any moment - the Constitution of the Republic of Serbia is prohibiting the prime minister from getting married."
"We can use her as a symbol of our struggle, which gives us much more space, especially media space, for the things we want to achieve," he concluded. Read more via b92