ATAC-seq is a high-throughput technology that defines and quantifies chromatin accessibility by analyzing Tn5 transposase enzymes. ATAC-seq is used to map chromatin accessibility genome-wide and to identify regions of transcription-factor binding and nucleosome position. As such, ATAC-seq is a new generation tool used in biomedical research to measure and articulate the pathogenesis of major diseases, to demonstrate the pharmacology of current drugs, and to guide the development of new drugs and the function of biomarkers. In this review, we summarize the current applications and advantages of ATAC-seq, and define its prospective contributions related to the regulatory mechanism of gene expression to identify and manage complex disease while elucidating and guiding future research references and strategies.