Changes in insect communities are one of the best indicators of environmental changes. A survey was conducted using the Flight Interception Trap (FIT) method to check the changes of species composition and abundance of silphids at Mt. Sokrisan National Park from April to October in 2003 to 2007. A total of9,704 individuals of six silphid species were examined by FIT. Among them, Nicrophorus quadripunctatus was the most dominant species with 8,763 (90.3%) individuals. There were only 971 (9.7%) individuals of the other five species. The seasonal abundance of silphids peaked in July and August. The annual abundance has decreased gradually since 2004. Therefore, the changing patterns of species composition and abundance of silphids checked by long-term monitoring could be used as environmental indicators which indirectly show the environmental changes of Mt. Sokrisan National Park.