〔Abstract〕 Alternative splicing(AS) is one of the important ways of post-transcriptional regulation, which can generate multiple mRNA isoforms from a single gene. In recent years, many studies have shown that AS can occur in almost all types of tumors, and the abnormal expression of splicing factors is related to the disease progression of tumor patients, which may become a potential marker for judging tumor progression. Therefore, this review summarizes the role, molecular mechanism, clinical relevance and treatment response of AS in tumors. It is found that AS can participate in the progression of malignant tumors by regulating tumor invasion, metastasis, apoptosis, cell metabolism, and promoting tumor immune escape and treatment resistance, which provides a theoretical basis for the clinical application of AS. The precise identification of tumor-specific AS and the development of small molecule inhibitors targeting specific AS isoforms may provide a new direction for precise and personalized cancer treatment.