The 70-year-old Hollywood titan made the announcement on Twitter, and in his usual fashion, kicked things off with a joke.
"As the Dude would say.. New S**T has come to light," he said, in reference to his character from "The Big Lebowski." "I have been diagnosed with Lymphoma. Although it is a serious disease, I feel fortunate that I have a great team of doctors and the prognosis is good."
The star also revealed that he's "starting treatment" for the cancer and promised to keep fans updated on his "recovery."
In a follow-up message, he thanked his followers for their support and encouraged them to vote.
"I’m profoundly grateful for the love and support from my family and friends," said Bridges. "Thank you for your prayers and well wishes."
He added: "And, while I have you, please remember to go vote. Because we are all in this together."
Per the Mayo Clinic, Lymphoma "is a cancer of the lymphatic system, which is part of the body's germ-fighting network."
"The Big Lebowski" is arguably Bridges' most well-known role. He won an Oscar in 2010 for "Crazy Heart" and has been nominated for six others, including his most recent nomination for playing a grizzled lawman in “Hell or High Water.”
Bridges has had a long career in Hollywood, his first appearance being an uncredited one as an infant in the 1951 film "The Company She Keeps," per IMDb.
He was last seen onscreen in 2018's "Bad Times at the El Royale."
The affable Bridges is considered Hollywood royalty, the son of actors Lloyd and Dorothy Bridges, who both died in 1998.
The Associated Press contributed to this report