Consumer prices grew 0.4 percent in April from the same month of last year, after a 0.4 percent on-year gain in March, a 0.5 percent rise in February and a 0.8 percent hike both in January and December 2014, according to the data compiled by the country's statistical office, Statistics Korea.
The 0.4 percent growth in April marks the lowest since a 0.3 percent on-year gain recorded in July 1999.
The Bank of Korea (BOK) has cut its inflation forecast for 2015 to 0.9 percent from an earlier estimate of 1.9 percent.