Both import and export prices fell in Korea last month due to the strengthening Korean won.
The Bank of Korea said Thursday that the nation's export prices fell 1.six percent in May from a month earlier, marking the lowest level in around six-and-a-half years.
The drop means local exporters are making less money when converting their export bills from dollars to won.
Import prices also dropped 1.7 percent in May from the previous month hitting the lowest level in more than four years.
The central bank said the Korean won strengthened by nearly 2 percent against the greenback in May.