Manning is required to serve one-third of the sentence before he becomes eligible for parole, meaning the 25-year-old would be 37 before he could be released.
He was sentenced by Judge Denise Lind, an Army colonel, and faced a maximum penalty of 90 years of imprisonment.
Last month Manning was convicted of multiple charges, including violations of the Espionage Act for copying and disseminating hundreds of thousands of classified documents to the anti-secrecy group WikiLeaks, while he was serving as an intelligence analyst at a forward operating base in Iraq.
At the sentencing phase of the court martial that ended last week, defense lawyer David Coombs tried to portray Manning as a well-intentioned but isolated soldier with gender-identification issues. He asked the judge to give him “a sentence that allows him to have a life.”
“He cares about human life,” Coombs said. “His biggest crime was he cared about the loss of life he was seeing and was struggling with it.”
Manning also addressed the court, apologizing and saying he was “sorry that I hurt the United States.”
Manning will receive a credit of 1,293 days for time served.
Last month, Lind found Manning not guilty of “aiding the enemy” in his release of 700,000 classified documents to WikiLeaks.
Earlier in the month, Lind rejected the defense motion to dismiss the key charge of aiding the enemy, but court observers believed the prosecution still had failed to prove that the Army private intentionally assisted enemies and harmed the U.S. military.
In her earlier ruling, Lind said the government had provided enough evidence to show that Manning “actually knew he was dealing with the enemy” by providing WikiLeaks with material that he knew would be posted on the Internet and thus be made available to al-Qaeda and other terrorist organizations. She cited his extensive training as an intelligence analyst and the sheer volume of records that were leaked as reasons to allow the charge to stand.
“He was knowingly providing information to the enemy,” Lind said.