Hong Kong Butterfly Inventory is the first citizen-initiated butterfly database in Hong Kong, established by “Butterfly Monitoring Team” formed by hundreds of secondary teachers and students. Starts from 2004, they are assigned to five butterfly hot spots to record the number of butterfly species. The date collected could help to understand the changes of local butterflies and ecological environment.   From 2004 to 2007, “Butterfly Monitoring Team” recorded 184 species of butterflies which is equivalent to 80% of butterfly species in Hong Kong. Among them, there are at least 11 Very Rare species and 34 Rare species.