The invention belongs to the technical field of oil and gas field reservoir reformation, and particularly relates to an oil well horizontal well oil jacket simultaneous injection type double-sealing single-clamping volume fracturing tubular column and a fracturing method thereof. The tubular column comprises an oil tube, and the tail end of the oil tube is sequentially connected with a packer, a check valve, a perforated tube and a guide centering device. A pressure transmitting ejector is connected between the packer and the oil tube. A second packer, a third packer and an annular injection valve are connected in series to the oil tube. The second packer is placed above the pressure transmitting ejector, the third packer is placed above the second packer, and the annular injection valve is placed above the third packer and is connected to the oil tube in series next to the third packer. The problems that a common double-sealing single-clamping staged fracturing technology is only suitable for oil tube injection fracturing construction in the prior art, fluid friction is large, and construction displacement cannot be improved easily can be solved, liquid flow is injected into the oil tube and a casing pipe at the same time, and layer-by-layer layered volume fracturing construction of an oil well horizontal well can be achieved from bottom to top.