Carbon fiber reinforced composite material for epoxy resin composition, a prepreg and carbon fiber reinforced composite material

Excellent mechanical strength under severe use environments, such as low temperature, high temperature moisture under, obtained using a suitable carbon fiber reinforced composite material as a structural material, an epoxy resin composition for obtaining this, and the epoxy resin composition to provide a prepreg. At least the following components [A], an epoxy resin composition comprising [B], and 20-80 mass% of [A] with respect to the blended epoxy resin per 100 wt%, the [B] a carbon fiber reinforced composite material epoxy resin composition which comprises 10 to 50 mass%. [A]: wherein the epoxy resin ## STR1 ## having the structure represented by (1) [B]: 4-membered ring or more ring structures of a two or more, epoxy resin having one amine type glycidyl group or ether type glycidyl group directly bonded to the ring structure