<p>The increasing demand for strategic mineral resources, together with the need for low-carbon and environmentally responsible extraction technologies, has made the efficient utilization of salt-lake resources an urgent research priority. Salt-lake brines contain abundant Li, Na, K, Cs, B, U, and other valuable elements, but their high salinity and complex multi-ion matrices pose major challenges to selective separation. Covalent organic frameworks (COFs), a class of crystalline porous polymers with designable skeletons, tunable pore environments and modifiable functional sites, offer a promising platform for element extraction from salt lakes. This review summarizes recent advances in the design of COFs for salt-lake resource recovery, with particular emphasis on functional-site engineering, pore regulation, ion-recognition mechanisms and representative applications in the capture and separation of lithium, potassium, cesium, boron, and uranium. Current limitations, including scalable synthesis, long-term stability, and the transition from empirical design to mechanism-guided material development, are also discussed. This review is expected to provide useful guidance for the rational design of high-performance COF materials for sustainable salt-lake resource utilization.</p>