The invention discloses an ultrahigh strength high-performance fiber concrete at C160 strength grade and a preparation method thereof. The concrete comprises the following components in parts by weight: 485 parts of cement, 82 parts of water, 1000 parts of macadam, 750 parts of fine aggregate, 70 parts of coal ash, 73 parts of rice hull ash, 102 parts of silica fume, 14.0 parts of water reducer, 9.5 parts of excitant, 1.6 parts of cellulosic fiber, 40 parts of hydroxy modified carbon nano tube dispersion liquid, 37 parts of graphene oxide dispersion liquid and 2.6 parts of de-foaming agent. The prepared concrete has higher toughness, durability, higher bonding strength with profile steel, compressive strength reaching up to 167.74MPa, breaking strength reaching up to 35.21MPa, splitting strength reaching up to 14.59MPa, bonding strength with profile steel reaching up to 7.54MPa and chloride penetration resistance grade at VI-grade. When the ultrahigh strength high-performance fiber concrete is applied to a profile steel concrete combined structure, the cooperative working property between the profile steel and the concrete is effectively exerted and the defects of poor bonding property of the profile steel and the concrete and incapability of fully utilizing the respective mechanical properties of the profile steel and the concrete can be overcome.