The invention discloses a graphene and ferroferric oxide dual-coated nanometer silicon composite material, a preparation method thereof and application thereof in lithium ion batteries, and belongs tothe technical field of lithium ion battery materials. The preparation method comprises the following steps: firstly carrying out mixing and ball-milling treatment on expansible graphite and a strongoxidant, then carrying out ball-milling on the treated expansible graphite, potassium ferrate and silica powder, and finally filtering, washing and drying to obtain the graphene and ferroferric oxidedual-coated nanometer silicon composite material. The material obtained in the invention can be used for cathodes of lithium ion batteries, and has relatively high specific capacity, preferable long-period cycle performance and excellent rate capability.