Wild boar have increased in recent years in Korea where damage to agricultural crops is considered as a social issue. The ecological studies on wild boar are essential for the effective management in the future. During May and December 2012, We collected 79 wild boar stomach samples from culling program implementation to reduce agricultural damage in Geochang County and analyzed stomach contents to figure out wild boar diet habit and which crop was preferred. There was seasonal variation in the diet. Plant foods represented up to 93.5% of the diet and were consumed more frequently than animal foods. Invertebrates occurred with high frequency but were underestimated in dry weight because they are rapidly digested. Agricultural crops consumed comprised mainly chestnuts(33%), rice(33%), and apples(24%). Agricultural crops are also a potentially important food resources for wild boar. The frequency of occurrence of earthworms was 50% of diet. Earthworm consumption generally increased in summer, and then decreased in winter. Our results show that wild boar can be considered an omnivore whose diet consists of plant and animal foods. To reduce wild boar agricultural damages, We have to focus on the prevention effort to rice paddy adjacent to chestnut forest and to apple orchard.