A cranial bone fixing device (A) and a surgical tool (B) are disclosed. The cranial bone fixing device (A) includes a lower fastening member (10) and a movable retaining assembly (20). The lower fastening member (10) includes a thread rod (12) having a first coupling portion (13) formed in an interior thereof. The movable retaining assembly (20) includes an upper fastening member (30) and a nut (40). The upper fastening member (30) includes a sleeve part (32) in which a first pivot portion (321) is formed. The nut (40) is screwed to the threaded rod (12). An upper end of the nut (40) is provided with a first positioning portion (42). An outer surface of the nut (40) is provided with a second pivot portion (41) mating the first pivot portion (321). The surgical tool (B) includes an outer sleeve (60) and an inner guide rod (50). A lower end of the outer sleeve (60) is provided with a second positioning portion (63) engagable with the first positioning portion (42). A lower end of the inner guide rod (50) is provided with a second coupling portion (51) engagable with the first coupling portion (13) of the threaded rod (12). Upper ends of the inner guide rod (50) and the outer sleeve (60) are provided with a third coupling portion (53) and a fourth coupling portion (62), respectively. Thereby, when the entire movable retaining assembly (20) is positioned by the outer sleeve (60), the movable retaining assembly (20) is set to be spaced from an outer surface of a cranium (70) by a spacing distance (x) to facilitate implantation and restoration of a cranial bone (72). The fixing device (A) can be quickly combined with the surgical tool (B). Only by rotating and displacing the outer sleeve (60) with one single hand, the fixing device (A) can be implanted and removed rapidly and effectively. The clinical operation is quite convenient and progressive.
