Enhancer is a special class of transcriptional regulatory elements in eukaryotic genomes. There are a large number of enhancer elements in eukaryotic genomes. Enhancers can interact with the promoters of target genes through the formation of chromatin loop, and regulate the transcription of target genes and the fate of cells together with the promoters. A large number of studies have shown that genetic variation, epigenetic modification and abnormal transcription factors can directly or indirectly lead to enhancer dysfunction or genome enhancer remodeling, and are closely related to the occurrence and progression of malignant tumor. In recent years, the rapid development of high-throughput sequencing technology and database has strongly promoted the depth and breadth of enhancer research. In this paper, the structural characteristics of enhancers, the regulation mode, the formation mechanism of abnormal regulation in the process of tumor occurrence and development, the main technical means of enhancer identification and common databases are briefly summarized and introduced.