Background: Cholangiocarcinoma is a malignant tumor of the biliary epithelium with poor prognosis due to late presentation. Histopathology is the gold standard for diagnosis but is invasive and limited in assessing tumor extent. Triphasic multidetector computed tomography (MDCT) offers a non-invasive alternative for evaluation. Objective: To assess the diagnostic role of triphasic MDCT in characterizing cholangiocarcinoma and to correlate imaging findings with histopathology. Methods: This cross-sectional study was conducted at Bangabandhu Sheikh Mujib Medical University, Dhaka, from September 2022 to August 2024. A total of 33 patients with suspected cholangiocarcinoma underwent triphasic MDCT. Imaging findings regarding lesion characteristics, location, growth pattern, vascular invasion, lymph node involvement, and enhancement patterns were analyzed. Histopathology was used as the reference standard. Diagnostic performance was calculated using sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy. Results: The mean age was 65.6 ± 7.51 years, with 66.7% males. Most tumors were perihilar (63.64%) and periductal infiltrating (60.6%). Ill-defined margins (69.7%) and delayed enhancement (81.82%) were common findings. Vascular invasion and lymph node involvement were seen in 27.3% and 39.39% of cases, respectively. MDCT showed a sensitivity of 89.66%, specificity of 75%, accuracy of 87.88%, PPV of 96.3%, and NPV of 50%, with a significant correlation with histopathology (p = 0.01). Conclusion: Triphasic MDCT is a reliable, non-invasive modality with high diagnostic accuracy for cholangiocarcinoma and is valuable for tumor characterization and staging.