The invention discloses a fracture orthotic device for bone surgery. The device comprises two hoops, an opening of each hoop is provided with an adjusting bolt, a plurality of supporting plates are arranged between the two hoops, the supporting plates are uniformly arranged in a circle to form a shape of an annular array, the inner side of the annular array is provided with a fixing cover, the fixing cover is composed of a plurality of pressing blocks, transversal elastic ropes and longitudinal elastic ropes, the pressing blocks are arranged in a circle to form a columnar structure, the pressing blocks in each same row / line are connected through a transversal / longitudinal elastic rope, each supporting plate is provided with a screw hole, and each screw hole is internally in threaded connection with a pressing push rod used for withstanding a corresponding pressing block. The fracture orthotic device for bone surgery has the advantages that the design of the structure is reasonable, thedevice can take the place of plaster to fix a fracture site of a leg bone of a patient, so that on one hand, interspace is reserved between the fixing cover and the fracture site, and the breathability is better; on the other hand, pressures on each pressing block can be adjusted through the corresponding pressing push rod, the device is suitable to various leg types, the device can fit the fracture site better and be fixed better, and the orthotic function is achieved.