The former police officer was handed the sentence by a Minnesota judge during a court hearing.
On April 20, 45-year-old Chauvin was found guilty of unintentional second-degree murder, third-degree murder and second-degree manslaughter after a trial.
Prosecutors had asked for a 30-year prison sentence – double the upper limit indicated in sentencing guidelines for a first-time offender.
Speaking through his attorney Eric Nelson, Chauvin had asked the judge to sentence him to probation, writing that the murder of Floyd was “best described as an error made in good faith.”
In a sentencing memorandum, prosecutors from the Minnesota attorney general’s office argued the crime had “shocked the conscience of the Nation”.
Earlier during a sentencing hearing, some of Floyd’s relatives gave emotional messages on a video.
As the hearing got underway, prosecutors had asked several of Floyd’s family members to address Hennepin County District Judge Peter Cahill.
Floyd’s seven-year-old daughter Gianna appeared in a video, in which she said: “I ask about him all the time.
“My daddy always used to help me brush my teeth.”
When asked what she would say to him if she could see him again, the young girl replied: “It would be I miss you and I love you.”
Floyd’s brother addressed Chauvin directly during his victim impact statement.
Terrence Floyd asked: “What was going through your head as you had your knee on my brother’s neck?”
He also told the judge he wanted the maximum sentence, adding: “We don’t want to see no more slaps on the wrist.
“We’ve been through that already.”
Chauvin briefly addressed the judge, saying: “At this time due to some additional legal matters at hand, I’m not able to give a full formal statement at this time.
“But very briefly though, I do want to give my condolences to the Floyd family.
“There’s going to be some other information in the future that would be of interest and I hope things will give you some peace of mind. Thank you.”
Video of Chauvin, who is white, kneeling on the neck of Floyd, a 46-year-old Black man in handcuffs, for more than nine minutes caused outrage around the world.
It sparked the largest protest movement ever seen in the US for several decades.
Last month, in a six page ruling, Judge Cahill ruled prosecutors had shown there were four aggravating factors that would enable him to hand down a longer prison sentence than guidelines would dictate.
He agreed Chauvin had abused his position of trust and authority.
The judge also agreed the former policeman had treated Floyd with particular cruelty; that he committed the crime as part of a group with three other officers; and that he committed the murder in front of children.
The three other police officers involved in Floyd’s arrest are due to face trial next year on charges of aiding and abetting Floyd’s murder.