The effect of the interfacial interaction between host-guest materials on energy transfer efficiency was investigated. Porous alumina membrane (PAM) was used as the host, and poly(N-vinylcarbazole) (PVK) and tris(8-hydroxyquinoline) aluminum (Alq(3)) were guest materials. The energy transfer between PVK and Alq(3) within a PAM shows greatly enhanced efficiency compared with that of the bulk film. Such high efficiency is ascribed to a lowered formation of the fully overlapped form of the PVK excimer, which is induced by strong interaction between the pendant carbazole rings of PVK and the A1 centers on the innerchannel surface of the PAM. The photoluminescence lifetimes of PVK become shorter with an increase in the Alq(3) concentration in both films and PAMs, due to the energy transfer. The mean distance between PVK and Alq(3) was estimated by using the Forster formula.