The clinical application of antisense oligonucleotide (ASO) therapeutics faces significant challenges, particularly those related to immunogenicity. To address these issues, researchers have introduced chemical modifications to the nucleic acid backbone and terminal structures of ASOs, thereby markedly improving their in vivo stability, target specificity, and resistance to nuclease degradation. In addition, advances in delivery systems and administration strategies have effectively enhanced delivery efficiency, enabling ASOs to better meet diverse therapeutic requirements. This review provides an overview of recent progress in the development, delivery, and immunological aspects of ASOs, with the aim of offering insights into chemical modification, delivery efficiency, and stability, and ultimately promoting the further advancement of ASO therapeutics in disease treatment.