Zebrafish xenograft model is of great importance in cancer modelling, especially xenografting of breast cancer. It facilitates real-time observation of tumor cell growth, metastasis, and interactions with the immune system, thus providing novel insights and experimental foundations for breast cancer treatment. Furthermore, the zebrafish xenograft model offers a valuable tool for high-throughput drug screening. This review provides an overview of how zebrafish xenograft model contribute in elucidating the underlying mechanisms in breast cancer development, as well as their use in screening anti-tumor drugs and conducting therapeutic research.