Because 12 months of detention are counted in the time of sentencing, the "rap boss" will have to spend 36 months in prison - that is, 3 years.
The judge also sentenced Diddy to five years of probation and a fine of $500,000 - the maximum penalty allowed.
When judge Arun Subramanian of the Federal court in New York (USA) delivered the verdict, Diddy bowed his head, covered his shoulders and held his hands tightly.
Before being sentenced, the rapper apologized to his ex-girlfriends, friends and family, calling his behavior "horrifying, embarrassing and medical".
He said that his children "done better" and the rapper did not fulfill his responsibility as a mother.
Judge Arun Subramanian emphasized that a long sentence is necessary "to send a message to both victims and victims that exploitation and violence against women must be truly held accountable".
The judges discussed Diddy's so-called "crazy parties" - his "white parties" - and dismissed the description of them as "intimate experiences with consensus or just stories about sex drugs and rock 'n' roll music".
Previously, during sentencing, US assistant attorney Christy Slavik told the judge that "Ddy's respect for the law is just a waste of words." He has scheduled a speech as early as next week because he predicted he would be eligible for release from prison.
"That is the pinnacle of pride. Even though he is serving a prison sentence for two federal crimes, he still does not fully understand why his actions brought him here, she said.
In July, Diddy was found guilty of two more serious crimes, sex trafficking and organized crime.
Prosecutors asked the judge to sentence the rapper to 11 years in prison, emphasizing that he "does not regret" his actions. While the defense said that Diddy only had to serve a sentence of no more than 14 months.
During the sentencing hearing on October 3, Combs' defense lawyers presented a 12-minute video showing him having talks to encourage children and participate in marathons to raise funds for education.
The 55-year-old rapper and music producer burst into tears, asking for leniency.
But the court eventually upheld the 50-month prison sentence, along with 5 years of probation after expiration. In response, Diddy's lawyers said they would soon file an appeal.
