Background: Metastatic hepatic focal lesions in breast cancer patients undergoing chemotherapy present diagnostic challenges. This study aimed to detect hepatic focal lesion in patient with cancer breast under chemotherapy. Methods: This observational cross-sectional study was conducted in the Radiology department of Tanta Cancer Center and included 50 adult female patients with primary breast cancer undergoing chemotherapy. Patients were subjected to a full history taking, clinical oncological examination, routine laboratory investigation, and multi-slice triphasic CT scans. CT images were analyzed for the location, number, size, shape, borders, and enhancement pattern of hepatic focal lesions. Histopathological examination results were used as the reference standard for the diagnosis of metastasis. Results: A total of 95 hepatic focal lesions were detected, with the majority in segment VIII (29.47%). Lesions displayed different enhancement patterns, with the most common being a complete ring (47.36%). Triphasic CT demonstrated a significant advantage in the prediction of liver metastasis compared to MRI, with a high positive predictive value (94.59) compared to MRI (97.36). The sensitivity and specificity of CT and MRI for diagnosing liver metastasis were 90% and 94.87% for CT, and 72% and 75% for MRI, respectively. Triphasic CT showed a high positive predictive value (94.59) compared to MRI (97.36). Conclusion: Multislice triphasic CT is a valuable diagnostic tool for the assessment of hepatic focal lesions in breast cancer patients undergoing chemotherapy.