The changes to the Telecommunications Business Act on Tuesday will ban those who run app markets from forcing a given payment system on a mobile content business by abusing market position, the South Korean news agency Yonhap reported.
The bill is expected to be signed by President Moon Jae-in, with his party have backed the change.
Any firms which do not fall into line can be fined up to 3% of the revenue they earn in South Korea. The Korea Communications Commission, the media regulator, will act as the enforcer.
Total sales from Google's Play Store in South Korea came to about five trillion won (US$4.2 billion) in 2020 while Apple's App Store netted 1.6 trillion won, according to figures from the Korea Mobile Internet Business Association.
In the US, a similar bill has been introduced in the senate to limit the control that Apple and Google wield over their app stores.
Yonhap quoted Ku Ki-bo, a professor of global commerce at Soongsil University, as saying: "The United States is currently reviewing measures against such market dominance, so it's unlikely for it to become a big problem for South Korea.
"The legislation will likely present an opportunity for local IT companies to expand their market presence."