The invention relates to a surgical bone screw comprising a shaft which has a bone thread and comprising a blocking means for interacting with a bone plate or for directly anchoring in the bone, in particular in the cortical bone. The surgical bone screw also comprises a screw head which has a rotationally symmetrical enveloping contour. The blocking means has a rib structure with at least one flank structure portion extending in the circumferential direction. According to the invention, the lateral surface of the enveloping contour has a constant or stepped concave progression, and the rib structure flank portion which extends in the circumferential direction is interrupted at least once in the circumferential direction, in particular multiple times, such that at least one elevation, in particular a plurality of elevations which are spaced in the circumferential direction, is produced in order to interact with the bone plate or with the bone in a blocking manner.