Growing population along with adverse phenomena such as climate change, limited resources, habitat destruction, and emerging diseases will present unprecedented challenges to our food safety and security over the coming decades. Efficiently dealing with these challenges will involve a thorough understanding of the molecular basis of phenotypic variation in our agriculture and aquaculture species. Selective breeding, combined with the latest advancements in genetic and genomic technologies, has helped substantially improve the quantity and quality of products from our farmed plants and animals. However, there has been considerable attention devoted to the potential use of epigenetic information in improving the traits targeted for selection in recent years. Epigenetic marks can be modulated through environmental cues and play essential roles in regulating different aspects of cell-specific gene expression and phenotypic plasticity. This chapter begins by presenting a brief overview of advances in genomic technologies related to selective breeding in aquaculture species. We then introduce the concept of epigenetics in breeding and how it might help improve our genetic estimates. The transgenerational inheritance of epigenetic marks, their possible use as biomarkers, along with some existing gaps, challenges, and potentials for future applications, will also be discussed.