Abstract: WD repeat domain 1 (WDR1) is a highly conserved cytoskeleton-associated protein that plays a crucial role in physiological processes such as actin cytoskeleton remodeling, dynamic regulation of intercellular junctions, cell division, and migration. WDR1 exhibits abnormal high expression in various malignant tumors, including breast cancer, ovarian cancer, and thyroid cancer, and has been demonstrated to significantly promote the invasive and migratory capabilities of tumor cells, suggesting its important role in the malignant progression of tumors. Moreover, the expression level of WDR1 is closely related to the clinical prognosis of patients with multiple malignant tumors. Especially in patients with esophageal cancer and osteosarcoma, its high expression often indicates a poor overall survival rate. WDR1 can promote tumor initiation and progression by regulating the Wnt/β-Catenin signaling pathway and the Hippo-YAP signaling pathway. Meanwhile, its expression is also subject to multi-level regulation by transcription activation factors and long non-coding RNAs (lncRNAs), thereby influencing the proliferation, migration, and other biological behaviors of tumor cells. Additionally, WDR1 can further drive the invasive growth and metastatic potential of tumors by regulating the epithelial-mesenchymal transition (EMT) process. This article aimed to systematically review the research progress in recent years regarding the biological functions and molecular mechanisms of WDR1 in tumor initiation and development, with a view to providing new theoretical foundations and research directions for the early diagnosis, prognosis assessment, and individualized treatment of clinical tumors.