Abstract: The unique characteristics of microalgae give themselves a natural advantage in drug delivery systems. As a type of natural active substance, microalgae and their outer vesicles have good biocompatibility. Due to their unique morphological structure and surface characteristics, they can achieve direct drug loading. The efficiency of drug delivery can be further improved by simple modification of the surface of microalgae. The multifunctional bio-hybrid micro-nano robot constructed on this basis has the potential for transformation in clinical treatment. We provide a review of the research progress of drug delivery systems of microalgae, their applications in disease treatment, as well as their prospects and future challenges.