The species diversity of macrolepidoptera (larger species of moths) was surveyed using light traps at forests near the Forest Environmental Research Institute located in 9 provinces (Gyeonggi, Gangwon, Chungbuk, Chungnam, Jeonbuk, Jeonnam, Kyeongbuk, Kyeongnam, Jeju) in 2012. Sampling was conducted weekly or biweekly from April to October. Using light traps in 8 forests, 2,961 individuals belong to 530 species from 20 families were collected. The species richness between study sites ranged from 4 (Kyeongnam) to 258 (Chungbuk). Similarly, abundance was the highest at Gyeonggi (1,235 individuals) and lowest at Kyeongnam (11 individuals). Species diversity (H’) was the highest at Chungbuk (5.14) and lowest at Kyeongnam (1.29). Composition of macrolepidopteran species also changed seasonally, showing regional variations. Dominant species in 9 study sites were Lamoria glaucalis in Gyeonggi, Ivela auripes in Gangwon, Idiotephria amelia in Chungbuk, agrotis tokionis in Chungnam, Acosmeryx naga in Jeonbuk, Glyphodes perspectalis in Jeonnam, Spodoptera depravata in Gyeongbuk, Xestia dilatata in Gyeongnam and Lithosia quadra Jeju. Among the species, Ivela auripes, Lamoria glaucalis, and Glyphodes perspectalis were known to be sporadic forest insect pests. Therefore, continuous monitoring can be needed to prevent the potential outbreaks of such insect pests.