Simple SummaryN6-methyladenosine (m6A) modification is among the most common and conservative RNA modifications in eukaryotes. The deposition of m6A on RNA is carried out by methyltransferases. As a regulatory subunit of methyltransferase, WT1-associated protein (WTAP) has gradually received attention in recent years. WTAP has been found to be expressed abnormally in a large number of cancers and affects cancer progression and prognosis. In this review, we propose a new perspective on the impact of WTAP on the occurrence and development of cancer, summarize the functional classification of WTAP in cancer, and envision potential therapeutic prospects.AbstractCancer is a grave and persistent illness, with the rates of both its occurrence and death toll increasing at an alarming pace. N6-methyladenosine (m6A), the most prevalent mRNA modification in eukaryotic organisms, is catalyzed by methyltransferases and has a significant impact on various aspects of cancer progression. WT1-associated protein (WTAP) is a crucial component of the m6A methyltransferase complex, catalyzing m6A methylation on RNA. It has been demonstrated to participate in numerous cellular pathophysiological processes, including X chromosome inactivation, cell proliferation, cell cycle regulation, and alternative splicing. A better understanding of the role of WTAP in cancer may render it a reliable factor for early diagnosis and prognosis, as well as a key therapeutic target for cancer treatment. It has been found that WTAP is closely related to tumor cell cycle regulation, metabolic regulation, autophagy, tumor immunity, ferroptosis, epithelial mesenchymal transformation (EMT), and drug resistance. In this review, we will focus on the latest advances in the biological functions of WTAP in cancer, and explore the prospects of its application in clinical diagnosis and therapy.