Epigenetics plays a crucial role in regulating gene expression, particularly in the field of transcriptomics. Dysfunctions in epigenetics have been identified as key factors in the development of cancer and numerous complex diseases. This book presents the most recent advancements in epigenetics omics technologies and their utilization in understanding the mechanisms of cancer and complex diseases. We hope that this book will serve as an enlightening resource, broadening the horizons of our readers and motivating them to explore the potential of integrating multi-omics data for investigating epigenetic regulations in different biomedical scenarios.