Supramolecular polymers are constructed through highly reversible and directionally specific non-covalent interactions between monomer units. This unique feature enables supramolecular polymers to undergo controlled structural reconfiguration and functional transformation in response to external stimuli, imparting them with high environmental responsiveness and self-healing properties. In particular, supramolecular polymers exhibit several specific advantages compared to conventional polymers, such as inherent degradability, the ease of preparation and the incorporation of functional units, and smart responsiveness to various biological stimuli. These characters make supramolecular polymers promising candidates for intelligent drug delivery systems in complex biological environments. In this review, we comprehensively summarize the latest developments and representative achievements of supramolecular polymers in drug delivery fields, focusing primarily on the design and synthesis, the properties and functionalities, and the practical applications of supramolecular polymers in small molecule drug delivery, gene therapy, and protein delivery. Finally, we highlight future research directions, focusing on multifunctionality, adaptability, and personalized therapy. We focus on recent studies that address key challenges in the field, providing rational polymer design, important properties, functionality, and understanding delivery strategies. These developments are expected to advance supramolecular polymers as new platforms of intelligent drug delivery systems, offering innovative solutions for the treatment of complex diseases.