He pleaded guilty in February for crimes relating to child pornography and soliciting sex from minors.
The star of hit Netflix series Cheer apologised to his victims and said he was “still learning who I am” at the hearing at a federal court in Chicago on Wednesday.
Prosecutors had urged the lengthy sentence, saying that Harris’ status as a popular celebrity had enabled him to “persuade and entice” his young victims to engage in sexual conduct.
Judge Manish S Shah told the social media star and cheerleading champion to consider the sentence an “expression of the seriousness of your crimes, tempered with some hope that all is not lost for you or for your victims, and that in the future some healing can occur”.
Harris, who has remained in custody at a federal detention facility since his arrest in September 2020, appeared in court for the sentence, which lasted around seven hours.
Addressing his victims before receiving his sentence, he said: “I am deeply sorry for all the trauma my abuse has caused you.
“I pray deep down that your suffering comes to an end.”
He added: “I’m not an evil person. I’m still learning who I am and what my purpose is.”
Notable figures listed as authors of character letters used by his defence included other stars of Cheer such as Navarro college head coach Monica Aldama, teammate Morgan Simianer, and the parents of Harris’ fellow cheerleader, Gabi Butler.
Harris, 22, previously pleaded guilty to one count of travelling with the intent to engage in illicit sexual conduct and one count of receiving child pornography.
Harris pleaded guilty to two of seven counts against him including persuading a 17-year-old to send him sexually explicit photographs for money.
The other count stemmed from a trip he took to Florida for the purpose of “engaging in illicit sexual conduct” with a 15-year-old.
US prosecutors agreed to drop the remaining five counts under a plea agreement.
A US child pornography charge carries a sentence ranging from five to 20 years and the second charge carries a maximum sentence of 30 years.
Harris, from the Chicago suburb of Naperville, was the breakout star of Cheer, a series following a cheerleading team from Navarro College in Corsicana, Texas, as it sought a national title.
He was arrested in September 2020 on a charge of production of child pornography.
Prosecutors alleged at the time that he solicited videos and images from two 14-year-old brothers.
In December 2020 he was indicted on more charges alleging misconduct in Illinois, Florida and Texas.
According to the indictment, Harris allegedly solicited sex from minors at cheerleading competitions and convinced teenage boys to send him obscene photographs and videos of themselves.
Harris later admitted to FBI agents to asking a teenage boy to send him photographs of himself, and to requesting child pornography on Snapchat from at least 10 to 15 others he knew to be minors, according to the indictment.
The second series of Cheer addresses the investigation into Harris, and dedicates an entire episode to the incidents, titled “Jerry”.