A report from the state-run institute said Friday North Korea has likely accumulated 100 launchers for short-range missiles, 50 for medium-range missiles and 50 for long-range missiles.
South Korea previously estimated the communist state had no more than 94 missiles.
"It [North Korea] is especially focused on certain asymmetric areas that can pose a threat to South Korea and U.S. forces stationed in the South," KIDA researcher Kim Sung-kurl told the Yonhap News Agency.
Tensions rose after North Korea tested a long-range missile in December and then completed its third nuclear test in February, RIA Novosti said.
Notable deaths of 2014 [PHOTOS]