<p>Metastasis is the leading cause of cancer-related deaths. Understanding the molecular mechanism of tumor metastasis is of great significance to cancer research. However, the molecular diagnosis and treatment of cancer metastasis are limited. Emerging studies reveal that epigenetic dysregulation is a universal feature across all human malignancies, with aberrant epigenetic modifications playing a pivotal role in cancer metastasis. In this review, we comprehensively summarized the latest research progress of several epigenetic regulation, such as DNA methylation, RNA/histone modification and noncoding RNA-mediated processes, and the metastasis-associated processes, such as cancer cell epithelial-mesenchymal transition (EMT), migration and invasion. In particular, this review emphasizes the key molecules in epigenetic regulation and elucidates their regulatory mechanisms in tumor metastasis. Additionally, we highlight promising therapeutic strategies, including early-stage clinical trial therapies targeting DNA/RNA and histone modifications. These may also be beneficial in finding new targets for further prognosis and diagnosis of cancer metastasis.</p>