Abstract: Using the incipient wetness impregnation procedure, iron was loaded in the mesopores in MCM-41 microspheres.The hybrid microspheres were decomposed by heating，producing iron-containing MCM-41 spheres with nano iron-oxygen clusters or nano-sized iron oxide particles inside the mesopores. Comparative characterizations of the iron-containing MCM-41 with different iron contents was performed.The influence of iron source on the synthesis of iron-containing MCM-41 was studied.The samples loaded with iron acetylacetonate have 3—4 times of iron content than those loaded with iron nitrate. The highest iron confent in MCM-41 was 1 mmol•g-1.The specific surface area,pore volume and pore size of the MCM-41 microspheres decreased after iron loading.In the case of loading with iron nitrate, contraction of the MCM-41 skeleton was observed after calcination, but no similar change in the case of loading with iron acetylacetonate. As far as the iron-loading content and the influence of the iron-loading on the skeleton of the mesoporous material were concerned, toluene solution of iron acetylacetonate was superior to the aqueous solution of iron nitrate as iron source for the synthesis of iron-containing MCM-41.