Abstract: Objective: To analyze the anatomical features of the olfactory region and their clinical significance using ultrahigh-resolution computed tomography (U-HRCT). Methods: The imaging data of 59 patients (27 males, 32 females; aged 16–69 years) who underwent U-HRCT at the Department of Radiology, Beijing Chaoyang Hospital, Capital Medical University, between March and May 2026 were retrospectively reviewed. Through the U-HRCT images, the anatomical characteristics of the olfactory fossa, olfactory cleft, and adjacent structures were observed and analyzed. Results: Olfactory fossa depth ranged from 0.80 to 10.06 mm (mean, 5.06±1.74 mm), with no significant differences by sex or side. Keros types I, II, and III olfactory fossae accounted for 24.58%, 60.17%, and 15.25%, respectively, and 38.98% of patients presented with bilateral asymmetry in olfactory fossa anatomy. Olfactory cleft depth ranged 15.5–38.8 mm (mean, 26.78±3.99 mm). The width of the middle olfactory cleft (3.26±1.02 mm) was significantly narrower than that of the anterior (4.39±1.30 mm) and posterior (4.59±1.87 mm) regions (both P < 0.001). Correlation analysis revealed that the anterior olfactory cleft score was significantly correlated with the middle turbinate concha bullosa (P=0.044) and the posterior olfactory cleft score was significantly correlated with the superior turbinate concha bullosa (P=0.008). Comparing the obstructed and non-obstructed olfactory cleft groups revealed significant differences in the middle turbinate concha bullosa in the anterior region and the superior turbinate concha bullosa in the posterior region (P=0.020, 0.004). Conclusion: U-HRCT can clearly depict the fine anatomical structures of the olfactory region and objectively evaluate anatomical variations of the olfactory fossa and cleft, as well as the impact of the concha bullosa on the cleft structure. These findings provide reliable imaging references for the etiological analysis of olfactory dysfunction and preoperative risk assessment in sinus and anterior skull base surgeries.