A jury in Clark County, Nevada, deliberated for nearly three hours before finding Duane "Keffe D" Davis, 63, guilty of a single count of first-degree murder with a deadly weapon, capping an 11-day trial in a downtown Las Vegas courtroom.
Davis will face a maximum sentence of life in prison without the possibility of parole at his sentencing on October 13.
Davis told the judge "he plans to appeal this matter".
Several people in the gallery wiped away tears and hugged a prosecutor as the court adjourned on Monday.
Representatives of the Clark County District Attorney's Office and Davis' lawyer did not immediately respond to emails seeking comment.
Chief Deputy District Attorney Binu Palal told jurors in closing arguments that Davis acquired a gun and "went hunting" for Shakur and Death Row Records co-founder Marion "Suge" Knight after they beat up Davis' nephew earlier that night.
Police say they long suspected Davis but did not have enough evidence to charge him until he went public with his story in media appearances and a memoir, which, along with tapes of his secret meetings with investigators, make up most of the prosecution's case.
Davis' lawyer Michael Sanft told jurors during his closing argument that his client's story could not be corroborated by evidence and should not be trusted.
He also said the case was tainted by police corruption, mismanagement and missing files.
"You're reading a book that is fiction and not fact, but the state wants you to believe that this is somehow a confession," Sanft said, referring to Davis' 2019 memoir Compton Street Legend.
Over the past two weeks, prosecutors played hours of recordings for jurors in which Davis said he was enraged after Shakur and his entourage beat up Davis' nephew.
Davis and three other men, including his nephew, went looking for Shakur and his record executive Marion "Suge" Knight in a white Cadillac on the night of the beating, he told police during an unrelated investigation.
Davis said he passed a gun to the back seat, and when they found Knight and Shakur's car, one of the two men in the back opened fire.
Prosecutors have not named the shooter, and the three other men in the car have since died.
Under Nevada law, Davis can be charged with murder even if he did not pull the trigger.
Davis was a leader of the South Side Compton Crips, a Los Angeles-area street gang that feuded with rival gang Mob Piru, which was associated with Shakur and his record label Death Row Records.
Shakur's 1996 killing became a seminal moment in rap history and heightened hip-hop culture's violent image during "gangsta" rap's heyday, an era defined by feuding between East and West Coast artists.
