Phosphorus is an essential nutrient for the growth of all living organisms. However, the improper discharge of phosphorus is also a key factor contributing to water eutrophication. With increasingly stringent phosphate emission limits and the sustained demand for phosphorus resources, the adsorption and recovery of phosphorus, followed by the high-value utilization of its products, represents a crucial future direction in this field. Adsorbents are key to achieving this goal. In recent years, magnesium-based adsorption materials have been widely studied due to their high affinity for phosphate, cost-effectiveness, and environmental friendliness. This paper reviews current research progress on phosphate removal performance, adsorption mechanisms, and the factors influencing phosphorus removal by magnesium-based functional materials. It provides an in-depth discussion of the material modification strategies for magnesium oxide, magnesium hydroxide, and various carrier-supported magnesium-based materials. Furthermore, the resource utilization methods for the recovery of adsorbed phosphate are analyzed. The phosphate adsorbed on the material can be recovered through elution, and the products after phosphorus adsorption can also be used for soil improvement, soil remediation, and water environment restoration. The applicable conditions for these resource utilization methods are analyzed, and the future research directions for subsequent phosphorus removal by adsorption are clarified. This work provides a reference for future research on phosphate removal by magnesium-based materials and phosphorus resource utilization.