His comments come three months ahead of general elections in April. Despite a recent property downturn, housing costs remain stubbornly high in the country and are cited as a key reason for discouraging marriage and childbirth.
"House prices rose more due to insufficient supply and that is still unresolved," Yoon told a discussion forum on television, calling the issue a "huge problem".
House prices in the capital Seoul were 15.2 times higher than the average annual income in 2022, up from 14.1 times in 2021, according to government data.
South Korea's real estate market has cooled since mid-2022 as demand dampened due to aggressive rate hikes by the central bank, with its policy rate currently at the highest since late 2008.
At the forum, measures to provide liquidity support for the construction sector were also discussed to help the financing of home building, the presidential office said.