Abstract: Objective: To explore the application value of virtual monochromatic imaging (VMI) technology with dual-layer detector spectral computed tomography (CT) in temporal bone CTV imaging. Methods: A retrospective analysis was performed on the imaging data of 44 patients who underwent temporal bone CT angiography and venography (CTA + CTV) examinations using Philips IQon CT. The data included conventional 140 kVp images from the CTV scanning sequence and 10 groups of virtual monochromatic images (40~120 keV at 10 keV intervals) reconstructed from the spectral data. For each group of images, the CT values of venous vessels in the confluence sinuum region were measured along with the CT values and standard deviation (SD) of the adjacent parenchyma at the same level,. The signal-to-noise ratio (SNR) and contrast-to-noise ratios (CNR) were calculated. Two experienced radiologists scored and compared the multiplanar reconstruction (MPR) and cerebral vascular intensity projection (CIP) images. Results: With an increase in the monochromatic energy level, the SNR, CNR, vascular CT, and SD values of the images decreased, with the VMI groups showing statistically significant differences with respect to the other groups. In the subjective evaluation of the MPR images, no statistically significant differences were observed between the scores of the conventional 140 kVp images and those of the 80 keV and 90 keV groups. Among them, the 50 keV VMI group achieved the highest MPR image score of 5 (4, 5). In the subjective evaluation of CIP images, there was no statistically significant difference between the scores of the conventional 140 kVp images and those of the 80 keV VMI group. All images in the 40, 50, and 60 keV VMIs groups met the diagnostic requirements, and their subjective scores were superior to those of the other groups, with scores of 3 (3, 3). No statistically significant differences were observed among the three groups. Conclusion: Virtual monochromatic images at (80~90) keV VMIs using dual-layer detector spectral CT were comparable to the 140 kVp images. VMIs with energy levels below 70 keV can effectively improve the visualization of venous vessels. Conventional 50 keV VMI is recommended as the optimal imaging modality for diagnosis.