ABSTRACT Small‐molecule drugs are crucial to human health. Yet, they often suffer from their low stability, poor water solubility, significant side effects, and rapid clearance rate from the human body, which limit their therapeutic efficacy in the treatment of chronic diseases. To address these issues, researchers have proposed the strategy of developing polymeric drugs. Multicomponent reactions (MCRs) are characterized by facile operation, modular reaction, and functional products, and have been served as powerful tools for synthesizing polymeric drugs. In this mini‐review, we mainly summarize recent studies of polymeric drugs based on MCRs. These polymer drugs have been applied in various fields as antioxidants, antitumor agents, metal chelators, and theranostic medicines. Meanwhile, we discuss the limitations of these studies and provide an outlook on future research trends.