Judge Peter Cahill handed down the sentence to Chauvin, 45, who fatally pinned Floyd to the ground during an arrest in May 2020. Chauvin held his knee on the neck of the 46-year-old for nine minutes and 29 seconds, ignoring Floyd's claims that he couldn't breathe.
Floyd's death triggered protests across the United States, after a video of the incident circulated online, placing renewed emphasis on racial justice issues around the world.
Chauvin, who pleaded not guilty in the trial, was convicted in April of all three charges: second-degree unintentional murder, third-degree murder and second-degree manslaughter.
Watch: Rev. Al Sharpton speaks at George Floyd's memorial. Post continues below.
Judge Peter Cahill imposed more than the 12-and-a-half-year sentence prescribed under state guidelines for second-degree murder, citing "[Chauvin's] abuse of a position of trust and authority and also the particular cruelty shown to George Floyd".
The judge also noted the sentence was not based on "emotion or sympathy", but he acknowledged the pain it caused all the families involved, especially the Floyd family.
Cahill also issued a 22-page sentencing order explaining his rationale for the punishment.
"Mr. Chauvin, rather than pursuing the MPD [Minneapolis Police Department] mission, treated Mr. Floyd without respect and denied him the dignity owed to all human beings and which he certainly would have extended to a friend or neighbour," the conclusion of the order read.