Expanding on his experience of the disease, the 46-year-old wrote about the early signs he noticed and how it has affected his relationships and family.
"The diagnosis came after years of living with the symptoms, misdiagnoses, and random questions all the time," the playwright and director of Fijian heritage said.
"Those closest to me have been unfaltering, discrete and kind. I've also learned not everyone can come on this journey with me," he wrote, adding he "buried it" as much as he could.
He was inspired to share his diagnosis because April is Parkinson's awareness month.
"It sucks but it [Parkinson's] doesn't define me," he added.
"It affects my movement, but over the last few years of living with it, I've worked with some of the world's best actors, dancers, stunties and athletes all over the world in the pursuit of stories to transcend this bull****."
The director is known for several high-profile projects, including the emotional movie No.2, which was released in 2006. Since then, he's helmed many notable films and TV series, including The Dead Lands, Daredevil, The Affair, The Rookie, and Titans.
And Fraser says the disease makes him a better director - but he believes there is work to be done to both find a cure and tackle the discrimination people who live with Parkinson's face.
"Today, I'm stepping out to join million of PD warriors with quivering hands who confront this challenge," he wrote in yesterday's Twitter thread.
"And in the meantime, I'm going to keep doing what I do," he declared.
