O.J. Simpson, the former football hero and actor whose good-guy image vanished when he was accused of murdering his former wife and her friend, will go free after serving nine years in a Nevada prison on charges stemming from an armed robbery, a state parole board ruled Thursday.

Simpson, who turned 70 this month, went before the board as a man convicted of taking a group of accomplices, two of them armed with guns, to a Las Vegas hotel room in 2007 to take hundreds of items from a sports memorabilia dealer. But it is the 1994 murders of Nicole Brown Simpson and Ronald Goldman, for which he was acquitted after the most-watched trial in history, that have cast the longer, darker shadow over his life and reputation.

After his conviction in the robbery case in 2008, a judge sentenced Simpson to nine to 33 years in state prison, meaning that he becomes eligible for parole for the first time Oct. 1. Based on his age and the fact that he has been a model prisoner, the Nevada Board of Parole Commissioners granted his release the first time it was considered, rather than denying parole and making him wait years for another chance.

Simpson, wearing a light blue denim shirt and looking considerably thinner than at a hearing in 2013, walked into the hearing just after 1 p.m. Eastern time. As the chairwoman of the parole board, Connie Bisbee, read the charges he was convicted of, he heaved a sigh and grimaced.

When Bisbee slipped and said Simpson was 90 years old, not 70, he said, “I feel like it, though.’’

Under questioning by parole commissioners, Simpson stuck to a version of the robbery that, as the board member Tony Corda said, “differs a little from the official record.’’

He insisted that the items he took from the memorabilia dealer, Bruce Fromong, whom he knew well, were his property. And he said he was not aware at the time that two of the men he took to the hotel room, whom he referred to as security guys, brandished guns.

He said he had never brandished a weapon at anyone, and never would.

“I basically have spent a conflict-free life,’’ he told the board.

Simpson’s daughter Arnelle Simpson testifiedon behalf of his family.

“We just want him to come home,’’ she said.

“My experience with him is that he’s like my best friend and my rock,’’ said Simpson, 48, who is the oldest of O.J. Simpson’s four children. “I know that he is remorseful. He is truly remorseful.’’

Arnelle Simpson and other members of his family live in California. O.J. Simpson lived most of his life in California, but in the years leading up to his conviction, he lived in Florida.

Parolees are required to appear for regular check-ins, submit to drug and alcohol tests, and cooperate with their parole officer, who can send violators back behind bars. In Nevada, the standard conditions of parole require the parolee to get permission before moving, refrain from drinking alcohol or carrying a weapon, and seek and maintain a job. Parolees may not associate with anyone who has a criminal record.

Parole board member David Smith spoke at a news conference after the decision of release was announced. He cited Simpson’s positive record in prison, a minimal record of prior convictions, his participation in programs addressing the behavior that led to incarceration, and family support as factors in his release.

Simpson’s felony convictions came 13 years to the day after a Los Angeles jury found him not guilty in the slayings of Nicole Brown Simpson and Goldman.

In 1997, in a civil trial, a jury found that Simpson was responsible for their deaths and awarded their families $33.5 million in damages. He has paid a tiny fraction of that amount.

The 2007 robbery occurred on the same day as the release of “If I Did It: Confessions of the Killer,’’ a book based on interviews Simpson gave, describing — in theory, hypothetically — how he could have carried out the murders.

One of his lawyers, Yale Galanter, has said that the charges filed against Simpson in the robbery case were excessive and has suggested that the prosecutors and jurors were influenced by the earlier murder case. Though jurors were prohibited from considering any outside factors, Galanter said he was concerned that the jury might not have been able to separate their strong feelings about Simpson and judge him fairly and honestly.

The Clark County district attorney at the time, David J. Roger, and members of the jury have insisted that their actions were no more than a reflection of the crimes Simpson committed in that Las Vegas hotel.