The jury returned the verdict in a Los Angeles courtroom shortly after 5 p.m. ET on Monday.
The six men and six women began their deliberations on March 26. They deliberated for about 30 hours.
Jurors had to decide whether Spector, 69 was guilty of second-degree murder or a lesser charge of involuntary manslaughter.
Spector, 69, was charged in the death of Lana Clarkson, 40, who was found dead, slumped in a chair in the foyer of Spector's home with a gunshot wound through the roof of her mouth.
A mistrial was declared in Spector's first trial in September 2007. After deliberating 15 days, jurors told Superior Court Judge Larry Paul Fidler that they were unable to reach a verdict. Spector was also charged with second-degree murder in that trial.
In closing arguments at the retrial, prosecutor Truc Do called Spector "a very dangerous man" who "has a history of playing Russian roulette with women -- six women. Lana just happened to be the sixth."
She pointed out that Clarkson bought new shoes on the day she died -- something a suicidal woman would not do.
Co-prosecutor Alan Jackson urged jurors to find justice for Clarkson. "Philip Spector is guilty of Lana Clarkson's murder. She is entitled to your justice," he said. "Philip Spector had his hand on that gun, and Lana Clarkson ended up dead.
In the 2007 trial, Spector's attorneys argued that Clarkson was depressed over a recent breakup and grabbed a .38-caliber pistol to kill herself while at Spector's home.
But prosecution witnesses painted Spector as a gun-toting menace. Five women took the stand to tell harrowing stories of being threatened with firearms by Spector. And his driver testified that he heard a loud noise and saw the producer leave the home, pistol in hand, saying, "I think I killed somebody."
The jury deadlocked, 10-2 in favor of conviction.
Spector's second trial began in October. Fidler ruled that jurors can consider the lesser charge of involuntary manslaughter against Spector.
If convicted of second-degree murder, Spector could face a prison sentence of 15 years to life, according to the Los Angeles County District Attorney's Office. An involuntary manslaughter conviction could bring a prison sentence of up to four years.
Clarkson starred in 1985's "Barbarian Queen" and the 1987 spoof "Amazon Women on the Moon" but was working as a VIP hostess at Hollywood's House of Blues at the time of her death.
Spector has won two Grammy Awards and was inducted into the Rock and Roll Hall of Fame in 1989, but he stayed out of the public eye for two decades before his 2003 arrest in Clarkson's death.
In the 1960s, he became famous as the man behind the "Wall of Sound," an instrumentally dense swirl of melody and percussion underlying such tunes as the Ronettes' "Be My Baby," the Righteous Brothers' "You've Lost That Lovin' Feeling" and Ike and Tina Turner's "River Deep, Mountain High."
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