A backlight module of an LCD device includes a plurality of fillisters formed in a reflection sheet and each of the fillisters having a reflection surface and a symmetrical axis. A plurality of point light source generators set in the fillisters, in which lights generated by the point light source generators are reflected by the reflection surfaces of the fillisters and the reflection sheet, and a profile of the point light source generators determines a shape of the fillisters. At least one diffuser plate installed on the reflection sheet for scattering the lights generated by the point light source generators and reflected by the reflection surfaces of the fillisters and the reflection sheet, in which an air space is formed between the diffuser plate and the reflection sheet.