Abstract: Fc region of a monoclonal antibody usually contains two N-glycosylation, which have a profound influence on its structure and function. Here, we review the relationship between various glycoforms and their impact on structure and function of monoclonal antibodies, along with the technologies for glycosylation analysis. In addition, some related Chemistry, Manufacturing and Controls (CMC) regulatory considerations are also discussed, such as specification improvement, biosimilarity assessment as well as comparability of pre- and post-process changes in glycosylation.