Stephen Bates made history on May 21 as the first Greens member elected for the seat of Brisbane.
He said his experience working poverty-wage jobs and coming out as gay shaped his politics.
"I spent my teenage years knowing I was gay and doing everything in my power to hide it," he told parliament on Wednesday.
"I made a promise to myself once I came out that if I ever found myself in a public role, that I will be open and proud of who I am.
"That I would be the person that I never saw growing up, because if I can even help one person out there, then this life would have all been worth it."
Mr Bates admitted sharing his story was harder than he thought it would be, and took a moment to compose his emotions.
He said he would use his time in parliament to advocate for those who have lost their voices due to the mental health crisis and shared the story of 24-year-old Maya Birch, who took her own life earlier this year.
"Maya is just one name in a long list of people who have had their lives cut short because of government inaction," Mr Bates said.
"The decisions we make in this place impact people's ability to survive.
"It is my job now to make sure that Maya's death was not in vain."
At 29 years old, Mr Bates is one of the youngest parliamentarians and said he hoped his election would inspire young people to run for office.
"I've heard many times that I'm too young for politics and I don't seem like a politician, which is a compliment, but it is these traits that got me here today," he said.
"This election has shown that people in this country are done with the status quo."
Mr Bates received a standing ovation from the crossbench upon the conclusion of his speech.
Lifeline 13 11 14
beyondblue 1300 22 4636
