Abstract: With the rapid development of biopharmaceuticals, therapeutic monoclonal antibodies (mAbs) are widely accepted due to their low side-effects and high therapeutic efficacy. Individual differences in the response to mAb drugs put forward new requirements for therapeutic drug monitoring of antibody drugs.Therefore, the need for accurate and robust bioanalytical methods is increasing.Recently, LC-MS/MS has been gaining increasing interest in the field of large molecules.In this article, the recent advances in this emerging field are reviewed, along with common issues and analytical approaches.Thus, this review article is helpful for better understanding the advance of LC-MS/MS technique in the field of therapeutic drug monitoring for mAbs.