Abstract: Objective: To conduct a comparative study on the effects of axial and helical scanning modes on image quality and radiation dose in cranial three-dimensional computed tomography. Methods Phantom study: The CTP515 low-contrast module and 528 high-contrast module of a Catphan600 phantom are scanned using clinical scanning protocols, and the image quality is evaluated using the Radia diagnostic software. Clinical study: A total of 298 cranial CT images obtained from five devices in our hospital from August 2024 to January 2025 are randomly selected for retrospective analysis. Among them, 147 cases in group A are scanned in the helical mode, and 150 cases in group B are scanned in the axial mode. All CT devices are used in both groups. The contrast-to-noise ratio, which is an objective index of the transverse, coronal, and sagittal plane images of the two groups, is calculated, and the image quality is scored subjectively. Statistical analysis is performed on the subjective and objective indicators, and P < 0.05 indicates a statistically significant difference. The radiation dose-related indicators of the patients are analyzed using the Radimetrics software. Results In the transverse plane, the image quality obtained via axial scanning is better than obtained via helical scanning. Meanwhile, in the coronal and sagittal planes, the image quality obtained via helical scanning is slightly better than that obtained via axial scanning. Except for device 4, the volume-rendering images based on helical scanning are better than that based on axial scanning. Among them, the CNR of the transverse plane of device 1 indicates a statistically significant difference; the subjective scores of the coronal plane of devices 2, 3, and 5 show statistically significant differences; the CNR of the sagittal plane of device 4 indicates a statistically significant difference; the subjective scores of devices 2–5 in the sagittal plane show statistically significant differences; and the subjective scores of VR of devices 1, 2, 3, and 5 indicate statistically significant differences. The differences in scan length, DLP, and ICRP103 between the two scanning modes of all devices exceed those of CTDIvol, with all being statistically significant. Conclusion When performing cranial CT examinations, the scanning mode selected significantly affects the image quality and diagnostic effectiveness. When only transverse plane images are required, axial scanning can provide an image quality that satisfies the requirements. Meanwhile, patients are exposed to a lower radiation dose if better-quality VR images are required. The transverse, coronal, and sagittal plane images satisfy the clinical diagnostic requirements, and the helical scanning mode is recommended. In certain conditions, a single-rotation axial-scanning mode can be used in conjunction with a wide-body detector.