<h4>Objective</h4>To assess the clinical value of the ALBI score and age in predicting trastuzumab resistance in patients with HER-2 positive breast cancer (BC).<h4>Methods</h4>A retrospective cohort study was conducted on patients with HER-2 positive BC treated with trastuzumab at the Department of Thyroid and Breast Surgery of Affiliated Hospital of Shandong University of Traditional Chinese Medicine from December 2017 to December 2023. Here, ERBB2 is linked to breast carcinoma.