"My son took his own life," his father, Walter Koenig, said in an emotional news conference in the park.
The actor's body was found about 11:30 a.m. in a heavily wooded area just off a bridle path in 1,000-acre Stanley Park, a favorite place for Koenig to frequent during his visits to Vancouver.
The body was found by a private search team of his family and friends. His father was in the midst of searching when he received a cell phone call from other searchers who discovered the body.
"I went to the site," Walter Koenig said, adding that's when he discovered his son had committed suicide.
Police and his family declined to comment on how Koenig took his life.
Koenig, 41, disappeared on Feb. 16 while traveling to the British Columbia city. Mounted officers had been searching the park, but didn't see the body amid the trees.
The announcement came a day after Koenig's father, who is also an actor – he starred as Mr. Chekov in the original Star Trek TV show and movies – made an emotional televised plea to his son to let the family know he was okay.
The younger Koenig, who played Kirk Cameron's pal Boner on the hit '80s sitcom, had long battled depression, his family said. He had cleared out his Los Angeles apartment about three weeks ago before traveling to Vancouver, where he once lived.
The elder Koenig was joined at the press conference by his wife. They put out a plea to anyone suffering depression as their son had to fight hard not to give up hope.
"If you can't handle it anymore, you know, if you could learn anything from this, is that there are people out ther who really care," said Walter Koenig.