Assessing the environmental carrying capacity for salt lake resources is essential for promoting sustainable development and use. A system dynamics (SD) model was employed to investigate the interrelationships among the economy, water resources, mineral resources, and the environment of Qaidam Salt Lake, scientifically focusing on the developmental requirements for potash and lithium resource development. An integrated evaluation system was developed to measure resource and environmental carrying capacity. Four different development scenarios were simulated to analyze the development tendencies of resource and environmental carrying capacity from 2021 to 2050, with early warnings issued. The results showed that: (1) The integrated carrying capacity of water resources and the environment initially declines before experiencing a subsequent increase. The water resources carrying capacity remains non-overloaded, while the environmental carrying capacity shows signs of overload. (2) By 2050, the carrying capacity for potash is projected to range from 7.91 to 9.17 million tons, whereas the carrying capacity for lithium is expected to range from 0.25 to 0.26 million tons. (3) Under the Business As Usual (BAU) and Increased Demand Scenarios (IDS), orange or red warnings are predicted during 2027-2044 and 2026-2050, respectively. In contrast, the Resource-saving Scenario (RSS) and Technology Enhancement Scenario (TES) result in lower environmental pressure, triggering only up to yellow warnings. A comprehensive assessment of resource consumption, environmental protection, and economic development shows that the TES scenario is most conducive to regional sustainable development. The findings provide a scientific basis for evaluating resource development levels and mitigating risks associated with resource depletion and environmental degradation due to over-exploitation. Furthermore, they contribute to sustainable management strategies for Qaidam Salt Lake and serve as a reference for similar regions.