Hollywood icon Peter Fonda is easy riding into the sunset -- the veteran actor died Friday ... TMZ has learned.

A rep for Peter confirms he passed Friday morning at his his home in Los Angeles, and was surrounded by family. We're told the official cause of death was respiratory failure due to lung cancer -- and he had been in and out of the hospital recently.

Peter, is Jane Fonda's brother and the son of Henry Fonda. The family released a statement, saying, "In one of the saddest moments of our lives, we are not able to find the appropriate words to express the pain in our hearts."

They added, "While we mourn the loss of this sweet and gracious man, we also wish for all to celebrate his indomitable spirit and and love of life."

Peter's most famous for his iconic role in the 1969 counterculture classic, "Easy Rider" ... which he co-wrote and produced. He also costarred with Dennis Hopper and Jack Nicholson.

The 50th anniversary of the film just past on July 14th, and Peter was planning a concert and screening for September to celebrate.

He got an Oscar nominatiion for writing "Easy Rider." He was also nominated for Best Actor for his role as a beekeeper in "Ulee's Gold" in 1997.

Most recently, Peter won a Golden Globe in 2000 for "The Passion of Ayn Rand."

He was married 3 times. His most-recent wife was Margaret DeVogelaere.

Our photogs last saw Peter in June 2018, and he was fired up about President Trump's administration. He was celebrating the fact Paul Manafort was going to prison.

Play video content 6/16/18 TMZ.com

Peter was 79.

RIP