The invention relates to a nanoporous-structure oxygen evolution catalyst with iridium oxide enriched on the surface and a preparation method for the oxygen evolution catalyst, and relates to the electrochemical field. The nanoporous-structure oxygen evolution catalyst with iridium oxide enriched on the surface can be obtained by adding a Co precursor into an Ir precursor and performing hydrolysisreaction, pyrolysis treatment and an acid etching process. The preparation method for the nanoporous-structure oxygen evolution catalyst with iridium oxide enriched on the surface comprises the following steps: adding the Co precursor into the Ir precursor, and performing hydrolysis reaction, pyrolysis treatment and the acid etching process, thereby preparing the catalyst, wherein conditions in apreparation process are controllable. The oxygen evolution catalyst which has the nanoporous structure, a high specific surface area and an IrO2 surface enrichment structure, has excellent oxygen evolution reaction catalysis activity and excellent stability. Besides, cheap Co is added so that the cost of the catalyst can be effectively reduced, and therefore, the oxygen evolution catalyst has a wide application prospect.