The invention provides a multi-component ultrahigh-entropy light-weight refractory composite material. Four light alloy elements including Mo, Ti, Al and Nb are used as a matrix, non-metallic elements including Si, C, N, B and O are introduced into the matrix, and the composite material contains multiphase ceramics including TiC, TiB2, SiC, Si3N4, BC, MoSi2, Nb2O5, SiO2 and the like, so that the high-temperature strength and oxidation resistance of the matrix are effectively improved, and the low-density, high-temperature, high-toughness and long-term oxidation resistance performance of alloy can be achieved. According to the multi-component ultrahigh-entropy light-weight refractory composite material, the composite material is prepared through powder mixing, forming, sintering and pre-oxidation, and the anti-oxidation time of the composite material in the air environment of 800-1500 DEG C is 100-300 h; the room-temperature tensile strength is 600-1000 MPa, and the ductility is greater than or equal to 10%; and the density is 4.5-5.5 g/cm<3>. The multi-component ultrahigh-entropy light-weight refractory composite material is suitable for the fields of aviation, spaceflight, weapons, nuclear energy, microelectronics and the like.