Given that pyrotinib has been proven to exert significant efficacy against HER2-positive advanced breast cancer in multiple Phase III studies, and the novel ADC drug disitamab vedotin has demonstrated potent anti-tumor activity, there remains insufficient real-world data on their sequential administration. This multicenter, prospective real-world study plans to enroll 500 patients with HER2-positive advanced breast cancer receiving first-line or second-line treatment. It aims to evaluate the efficacy and safety of sequential disitamab vedotin treatment after disease progression or intolerance to pyrotinib-based regimens (first-line: pyrotinib plus trastuzumab combined with chemotherapy; second-line: pyrotinib plus capecitabine). The primary endpoint is real-world second progression-free survival (rwPFS2), while secondary endpoints cover real-world progression-free survival (rwPFS), tumor response, overall survival (OS), time to treatment failure, safety profiles and patient-reported outcomes. It is currently expected to further validate the efficacy and safety of pyrotinib in patients with advanced HER2-positive breast cancer in the real-world setting, and to evaluate the efficacy and safety of recindopril trastuzumab following pyrotinib-containing regimens.