Yoon imposed martial law on the night of Dec. 3, sending troops and helicopters to the National Assembly. The decree was canceled after lawmakers voted against it.
Lawmakers will vote on the impeachment motion at a plenary session scheduled to begin at 4 p.m.
The vote comes a week after an initial bid to oust him failed last Saturday when most of ruling People Power Party (PPP) lawmakers boycotted the vote, preventing the required two-thirds quorum.
Opposition parties led by the Democratic Party filed a second bill Friday, labeling the martial law declaration an unconstitutional act of insurrection.
The motion is largely expected to be adopted this time.
Impeachment requires 200 votes in the 300-seat assembly. Opposition parties control 192 seats, and at least seven PPP lawmakers have pledged to vote for it.
If the motion is approved, Yoon's powers would be immediately suspended while the Constitutional Court reviews the case, a process that could take up to 180 days.
Prime Minister Han Duck-soo would serve as acting president during court deliberations.
If the court accepts the decision, Yoon will become the second South Korean president to be ousted by impeachment following Park Geun-hye's removal in 2017.
Park, the nation's first female president, was jailed for bribery and abuse of power in a corruption scandal involving her confidante.
In 2004, President Roh Moo-hyun was impeached by parliament over alleged election law violations. However, the Constitutional Court reinstated him.
If the court upholds impeachment, a new presidential election must be held within 60 days. DP leader Lee Jae-myung, PPP leader Han Dong-hoon, and Seoul Mayor Oh Se-hoon of the PPP are seen as potential candidates.
The leaders of the two parties have called for lawmakers to vote to remove Yoon.
"Impeachment is the quickest and most certain way to end the chaos," the opposition leader said Friday. "History will remember and record your choice," he added.
"The only way to suspend President Yoon's duties is through impeachment," Han said earlier this week.
The ruling party, which boycotted the session last week, allowed lawmakers to vote this time but did not change its party line opposing impeachment.
Yoon defended his martial law declaration Thursday, saying it was necessary to "eliminate pro-North Korean forces and protect South Korea's constitutional order." He vowed to fight until the end.
His martial law declaration has sparked massive protests across the country demanding his removal. An estimated 140,000 protesters demonstrated at boulevards near the National Assembly in Seoul last Saturday when the first impeachment vote was underway.
Yoon's approval rating has plummeted to 11 percent, the lowest during his presidency, according to Gallup Korea Friday.
Yoon faces probe on charges of rebellion. Police banned him from traveling abroad and tried to raid the presidential office.
Top officials in Yoon's government are under investigation, with former Defense Minister Kim Yong-hyun and two highest-ranking police officers arrested.
Prime Minister Han Duck-soo also faces his own scrutiny over alleged involvement in the martial law crisis. If Han were also removed, Deputy Prime Minister and Finance Minister Choi Sang-mok would assume the role of acting president.
Yoon took office in 2022 after narrowly defeating Lee. He was appointed prosecutor-general in 2019 by then President Moon Jae-in and built his political profile as he clashed with Moon's administration and investigated his allies.
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