The producer price index (PPI) stood at 109.6 in 2021, up 6.4 percent from the previous year, according to the Bank of Korea.
It marked the highest increase in 10 years since 2011, rebounding after falling 0.5 percent in 2020.
In December, the PPI was unchanged compared to the previous month.
The producer price for agricultural, livestock and fishery products advanced 2.6 percent in December from a month earlier.
Price among suppliers for electricity, natural gas and tap water increased 1.6 percent last month on a monthly basis, and the services price added 0.3 percent.
However, the producer price for industrial products, including oil products, decreased 0.6 percent in December from a month ago amid lower crude oil price in the final month of last year.