The producer price index stood at 104.14 in March, up 0.3 percent from the previous month, according to the Bank of Korea (BOK).
The index continued to rise for two months in a row as Dubai crude, South Korea's benchmark, gained to an average price of 66.94 U.S. dollars per barrel in March from 64.59 U.S. dollars in February.
Price for industrial goods was up 0.4 percent last month. Coal and oil product prices picked up 5.5 percent, marking the highest since January 2017.
Prices for agricultural, livestock and fishery products gained 1 percent on a sharp rise in livestock price.
Services price added 0.2 percent in March from a month earlier, but prices for electricity, tap water and natural gas fell 0.1 percent.