The 64-year-old, once a scout for Manchester City and Crewe Alexandra, abused 11 boys aged eight to 15 between 1979 and 1990 on an "industrial scale", Liverpool Crown Court heard.
Bennell was charged in November 2016 after prosecutors received a file of evidence from Cheshire Police.
He had denied 48 alleged offences relating to 11 complainants, choosing not to give evidence in his defence during the month-long trial and appearing by video link from prison due to illness.
He had pleaded guilty to seven counts of indecent assault involving three boys.
In testimony, several victims estimated Bennell had sexually abused them on more than 100 occasions.
Jackie Lamb, from the Crown Prosecution Service (CPS), said Bennell was a "predatory paedophile" who groomed and abused young boys dreaming of a career in professional football.
"He claimed his accusers were making up stories about him following previous convictions and stories in the media but thanks to the evidence from his victims, the CPS and police were able to build a strong case to expose Bennell's denials as lies," Lamb said.
"Because of the scale of Bennell’s offending, the prosecution faced a number of challenges, including selecting charges which would adequately reflect the scale and seriousness of what Bennell did.
"The indictment before the court properly reflected that offending and will allow the court to sentence appropriately."
Bennell will be sentenced on Monday, according to the BBC.
Allegations of child sex abuse in English football from the 1970s through to the 1990s have shocked Britain and led to deep soul-searching in the game amid fears hundreds of young boys might have been involved.
(Reporting by Martyn Herman; editing by Andrew Roche)
