A bottom structure of a container comprises a bottom frame including two parallel bottom side rails and two bottom end rails transversally connected to the ends of the two bottom side rails, and one or more wood floors and one or more steel floors extending along the length direction of the bottom side rails, which are alternately arranged in parallel with the bottom side rails and fixed between the two bottom end rails, in which an upper surface of the steel floor is flush with an upper surface of the wood floor. The bottom structure in the present invention has the advantages of saving wood materials and having excellent rigidity.