Abstract: Cancer therapeutic drugs include traditional chemotherapy drugs, targeted therapy drugs, monoclonal antibodies, as well as novel antibody-drug conjugates (ADCs) and peptide-drug conjugates (PDCs). PDCs have demonstrated significant clinical advantages in cancer treatment, but they still face limitations such as poor stability and insufficient targeting specificity. In recent years, the application of multivalent targeting peptide strategies and dual targeting peptide strategies has significantly improved the targeting precision of PDCs. Meanwhile, molecular engineering approaches such as peptide cyclization, unnatural amino acid substitution, and fatty acid chain modification have effectively enhanced the in vivo stability of PDCs. These innovative strategies have markedly strengthened the pharmacological activity of PDCs and their therapeutic efficacy in tumors. Based on the structural characteristics and research progress of PDCs, this article systematically reviews the latest strategies for improving the targeting ability, stability, and cell membrane penetration efficiency of PDCs, aiming to provide a theoretical foundation and research insights for the development of PDC-based anticancer drugs with superior pharmacodynamic properties.