A back brace type surgery positioning apparatus is provided, which includes a back brace, a positioning mechanism and an operation-assisting member. The back brace has a main board configured to be disposed on the back of a patient, an abdomen pressing board configured to be disposed on the abdomen of the patient, a plurality of positioning members for connecting the main board and the abdomen pressing board, and a positioning base board disposed on the main board. The positioning mechanism is connected to the positioning base board and has a support rack, and first and second rotating arms pivotally mounted to and rotatable relatively to the support rack, and the second rotating arm is configured to secure a surgical tool in place. The operation-assisting member is fastened by the first and second rotating arms and configured to adjust the direction and position of the surgical tool.