The morbidity and mortality of gastrointestinal malignancies are the highest in the world. For patients with poor response to conventional chemotherapy, new treatment methods are urgently needed. In recent years, under the background of precision medicine, antibody-drug conjugates (ADCs) with high tumor specificity and potent toxicity have become a hot research spot in the field of biomedicine. However, due to the complex structure and mechanism of ADCs, its pharmacokinetic research is facing great challenges which are the biggest resistance to the development of ADCs at present. In this case, it is of great significance to understand the pharmacokinetic properties of ADCs and make use of it to improve the efficacy of ADCs in the treatment of gastrointestinal malignancies. Based on the basic composition and mechanism of ADCs, this review summarizes the pharmacokinetic properties of ADCs, discusses its recent advances in the treatment of gastrointestinal malignancies, in order to provide more references for follow-up research on ADCs.