Michael J. Fox received America's highest civilian honor Saturday ... after President Joe Biden awarded him the Presidential Medal of Freedom in an emotional moment.

The actor attended the ceremony at the White House Saturday ... alongside several other stars and high-profile Democrats who received the same honor from the 46th president.

Watch the clip ... Michael walks to centerstage with help from a man in uniform to stand alongside POTUS -- when a series of his accomplishments are read out.

Among them ... Fox's iconic characters Alex P. Keaton from "Family Ties" and Marty McFly from "Back to the Future."

However, a majority of the time during the speech was dedicated to the star's relentless optimism -- especially in the face of his battle with Parkinson's.

Michael was diagnosed with Parkinson's in the early 1990s ... and announced the news later in the decade while on the show "Spin City."

He's become an activist, raising money for people with the disease in recent years ... and gave fans an inside look at his life with it in the documentary "Still: A Michael J. Fox Movie."

Fox was joined onstage by music legend Bono, basketball star Magic Johnson and actor Denzel Washington ... all of whom were lauded for their talents -- and their activism as well.

President Biden's leaving office later this month ... and, he's finishing off his tenure by showing respect for some of the biggest names in Hollywood.