Abstract New methods were used to prepare a nearly stoichiometric Mn3O4 catalyst. The redox behavior of two kinds of Mn3O4 (i.e. the non‐ and nearly stoichiometric Mn3O4) were compared. The relations between the IR parameters, Mn/O stoichiometry and redox properties of Mn3O4 were established. It was found that the Mn/O stoichiometry but not IR parameters was closely related to the redox behavior of the compounds.