Jung Joon-young, 30, and Choi Jong-hoon, 30, were sentenced to six and five years in prison for rape at Seoul Central District Court on Friday.
The men will also each have to do 80 hours of “sexual violence treatment education” as part of their sentence.
Both men were members of online chat groups that shared secret sex tapes and made jokes about drugging and raping women, the court heard.
Jung’s conviction included charges for sharing videos he secretly filmed during the rape of one woman and while having sex with other women.
The musician, who rose to fame on a TV talent show, admitted distributing the videos, but claimed the sex was consensual in all cases.
Sentencing the musicians on Friday, judge Kang Seong-soo said: “The defendants are well-known celebrities and friends, but the chat they’ve had showed that they simply considered women as objects of sexual pleasure, and committed crimes that were extremely serious.
“Strict punishment is inevitable as the damage inflicted has not properly been recovered and the victims demand harsh penalties.”
Choi, a former member of South Korean boy band FT Island, denied raping the woman in one of the videos filmed by Jung.
He argued that he did not remember having sex with her and that if he had it was likely consensual.
Their case was one of several scandals involving sex crimes and other illegal activity that revealed a dark side of an industry at the centre of the global K-pop craze.
Lee Seung-hyun, a former member of K-pop group Big Bang who is better known by the stage name Seungri, is also on trial over accusations he paid for prostitutes for foreign businessmen to drum up investment in his business.
Lawyers for Jung and Choi could not be reached for comment.
Additional reporting by Reuters