Lee Jae-rock, 75, has about 130,000 followers at the Mamin Central Church in Seoul, reports the BBC.
He has denied all the allegations.
His victims had spoken of his "divine power" and said they felt compelled to do what he asked because "he was God".
Lee's church is regarded as a splinter cult by some mainstream Christian organisations.
He set up the Mamin Central Church in 1982 with only 12 followers. It has now grown to what is known as a mega church, with its huge headquarters and auditorium and a website with promises of miracles.
Earlier this year, three of his followers came forward with allegations that Lee called them to his apartment and forced them to have sex.
In total, eight women filed criminal complaints and he was arrested in May.
The court found Lee molested and raped the victims "tens of times" over a long period.
"Through his sermons the accused has indirectly or directly suggested he is the holy spirit, deifying himself," judge Chung Moon-sung told the Seoul Central District Court.
The victims believed him to be "a divine being who wields divine power", he said.
(With inputs from agencies.)