During a press conference the center held in response to Trump's announcement over Twitter, Rudy Akbarian said he was advised not to say what unit he works in but is part of the U.S. military.
"I am speaking as a proud trans service member," he said. "I enlisted in the military because I love my country, because I wanted to become a part of something greater than myself. I've been a service member for over five years."
He added that his superiors know about his status and that the military helped him find strength.
"The people in my chain of command know my transition, as do many of the soldiers who serve with me. The military has empowered me to channel the strengths that I never knew I had," he said.
Akbarian works at the center as an employment specialist and helps homeless LGBTQ youth find jobs.
Center CEO Lorri L. Jean said that Congressional leaders who called out Trump for his decision are not doing enough.
"Republicans and Democrats must rise up across the country in opposition to a president who would take us back and impose discrimination and bigotry rather than upholding our Constitution's promise of equality and justice for all," she said.
Later Wednesday afternoon, Akbarian addressed a group of people at the center as many transgender people became increasingly concerned about their employment.
"There is nothing about us being trans that makes us incapable of completing missions," he said.
He is one of more than 2,400 active transgender service members. Akbarian said serving in the military is more than just a job - it's their livelihood, their retirement and part of who they are.
Joshua Gershick, a transgender veteran, said Trump's message was clear.
"The message is - 'We don't want you. You're inferior. You're not worthy. You're not really a part of America,'" he said.
Attorney for the American Civil Liberties Union in the city also said they would sue the Trump administration, if necessary.
Trump announced the decision in a series of tweets Wednesday morning, which quickly resulted in reactions from celebrities and members of the LGBTQ community.
At the Pentagon, members of the staff of Defense Secretary Jim Mattis appeared to have been caught unaware by Trump's tweets. A Pentagon spokesman, Navy Capt. Jeff Davis, referred questions to the White House.
In a brief written statement, Davis said the Pentagon is working with the White House to "address" what he called "the new guidance" from the president. He said the Pentagon will provide revised guidance to Defense Department officials "in the near future."
During a White House press briefing in the early afternoon, press secretary Sarah Huckabee Sanders said it was a difficult decision but there was reason to enact the ban.
"This is a very expensive and disruptive policy that erodes military readiness and unit cohesion," she said.
Some lawmakers do not want taxpayers to pay for gender reassignment surgery, but a 2016 Rand Study concluded gender transition health care coverage for transgender military members would increase the defense department's costs by as much as $8.4 million. That is only a tiny fraction of the Pentagon's overall $49.3 billion health care expenditures.
The Washington Post also did an analysis on military spending, finding that 10 times more money is spent on Viagra than gender reassignment surgery.
Transgender service members have been able to serve openly in the military since last year, when former Defense Secretary Ash Carter ended the ban. Since last Oct. 1, they have been able to receive medical care and start formally changing their gender identifications in the Pentagon's personnel system.
During his election campaign, Trump occasionally presented himself as a potential ally of gays and lesbians, promising to be a "real friend" of their community.
The Associated Press contributed to this report.