Abstract: Background Amidst the intensifying backdrop of global climate change, a global paradigm shift from conventional, slow-onset droughts to flash droughts is underway. As rapidly developing and highly destructive extreme events, flash droughts pose a severe challenge to global socioeconomic and ecological security. Methods This paper first traces the evolution of the flash drought concept, clarifying the current definition framework, which centers on three core elements: rapid intensification, drought onset, and adverse impacts. It further deconstructs the physical mechanisms, demonstrating how global change non-linearly amplifies flash drought risk through synergistic interactions across the atmosphere, ocean, and land, and examines the core scientific questions within this framework. Results Observational and modeling evidence indicates a significant acceleration in the global intensification rate of droughts over recent decades, with future scenarios projecting a continued rise in the frequency and intensity of flash drought events. The destructive potential of flash droughts is compounded by their concurrence with other extreme events, such as heatwaves, leading to compound disasters and cascading impacts across agriculture, ecosystems, and water resources. Conclusions In light of these challenges, the paper concludes by exploring adaptation and mitigation strategies for flash droughts. It highlights the urgent need to: (1) establishing high-resolution, multi-indicator integrated monitoring and early warning systems; (2) overcoming forecasting limitations at sub-seasonal to seasonal timescales; and (3) establishing a comprehensive risk governance framework from local to global scales. This article aims to advance scientific understanding of flash droughts, strengthen disaster risk reduction capacities, and provide a scientific basis for climate-related policy formulation.