Among various microporous and mesoporous materials investigated, the Li+-exchanged zeolite faujasite has been found to be the most efficient support of iron catalyst for producing C-5(+) hydrocarbon fuels via Fischer-Tropsch synthesis. The location of iron species in the catalyst is a key issue in obtaining high selectivities to C-5(+) hydrocarbons. It is proposed that the Li+ cation and the supercage structure of zeolite faujasite both play important roles in improving the selectivities to C-5(+) hydrocarbons over the Fe catalyst.