The 81-year-old was convicted in April of three counts of aggravated assault after drugging and sexually assaulting Andrea Constand in 2004.
Sentencing Cosby to between three and 10 years at Montgomery County Courthouse, Pennsylvania, Judge Steven O’Neill told him: “This was a serious crime. Mr Cosby, this has all circled back to you. The day has come, the time has come.”
The judge’s “predator” ruling came on the second day of a two-day hearing before sentencing Cosby for the attack at his Philadelphia home.
It means Cosby – once dubbed “America’s dad” for his role as Dr Cliff Huxtable on The Cosby Show – must undergo counselling for life and report to authorities every three months.
His name will appear on a sex offender register sent to neighbours, schools and victims. Cosby was denied bail.
The defence earlier indicated that it would appeal the conviction.
Ms Constand, 45, became friends with Cosby while coaching a women’s basketball team where he had been a major supporter and donor. At an earlier hearing, she described how her “mentor” Cosby gave her pills that left her “frozen” and unable to stop his assault.
In an impact statement released yesterday, Ms Constand wrote that she stopped eating, sleeping and socialising in the wake of the assault.
“Bill Cosby took my beautiful, healthy young spirit and crushed it. He robbed me of my health and vitality, my open nature and my trust in myself and others,” she said.
Cosby – who earlier was seen smiling and joking with his spokesman and sheriff’s deputies in the courtroom – declined an opportunity to address the court before the sentence was handed down.
At least seven women who have accused Cosby of similar acts were present in the courtroom, but his wife of 54 years, Camille, was not.
In the years since Ms Constand first went to authorities in 2005, more than 60 women have accused Cosby of sexual misconduct, though none of those claims have led to criminal charges.
On Monday there had been legal debate over whether Cosby deserved the violent predator label.
His lawyer Joseph Green, had asked for house arrest saying Cosby – who is legally blind – was too old and helpless to do time and there was “no reasonable prospect” of his reoffending.
But psychologist Kristen Dudley testified he showed signs of a mental disorder and was likely to reoffend.