Our efforts to combine the combinatorial technology and microstructure analysis to develop catalysts for proton exchange membrane fuel cell (PEMFC) technology have been described. This offers the realization of “materiomics” in comprehensive material research. Catalyst technologies are indispensable for wide use of PEMFC, which are regarded as the low emission and highly efficient energy conversion device for the next generation. We have applied the combinatorial method for the hydrogen production and/or purification of catalysts, and anode catalyst investigations. The catalyst library consisting of precious metals loaded on various metal oxides was tested for water gas shift reaction and steam reforming of methanol and/or DME. Various metal oxides added to platinum loaded on carbon were screened for anode catalysts. The microstructure of each catalyst was analyzed by employing scanning electron and/or transmission electron microscopy. This paper mainly describes the catalysis screening results of above reactions that form a part of “materiomics”.