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In this study, a global variable‐resolution modeling framework of atmospheric dust and its radiative feedback is established and evaluated. In this model, atmospheric dust is simulated simultaneously with meteorological fields, and dust‐radiation interactions are included. Five configurations of global mesh with refinement at different resolutions and over different regions are used to explore the impacts of regional refinement on modeling dust lifecycle at regional and global scales. The model reasonably produces the overall magnitudes and spatial variabilities of global dust metrics such as surface mass concentration, deposition, aerosol optical depth, and radiative forcing compared to observations and previous modeling results. Two global variable‐resolution simulations with mesh refinement over major deserts of North Africa (V16 km‐NA) and East Asia (V16 km‐EA) simulate less dust emissions and smaller dry deposition rates inside the refined regions due to the weakened near‐surface wind speed caused by better resolved topographic complexity at higher resolution. The dust mass loadings over North Africa are close to each other between V16 km‐NA and the quasi‐uniform resolution (∼120 km) (U120 km), while over East Asia, V16 km‐EA simulates higher dust mass loading. Over the non‐refined areas with the same resolution, the difference between global variable‐resolution and uniform‐resolution experiments also exists, which is partly related to their difference in dynamic time‐step and the coefficient for horizontal diffusion. Refinement at convection‐permitting resolution around the Tibetan Plateau (TP) simulates less dust due to its more efficient wet scavenging from resolved convective precipitation around the TP against coarse resolution. Plain Language Summary: Mineral dust plays an important role in Earth's climate system. Numerical simulation of dust and its impacts on a regional scale still has large uncertainties, partly due to the relatively coarse horizontal resolution. Limited‐area simulation at relatively high resolution can generally better characterize dust and its impacts on a regional scale; however, lateral boundary conditions may introduce some numerical issues and constrain regional feedback, such as dust‐cloud and dust‐radiation interactions, to large‐scale circulation. In this study, a novel modeling framework of atmospheric dust and its climatic feedbacks with the capability of global variable‐resolution simulation is established and evaluated. The model produces reasonable global spatial distributions of dust compared to observations and previous studies. The difference between the simulations at global quasi‐uniform resolution and global variable resolution with regional refinement over East Asia and North Africa is significant, particularly with refinement at convection‐permitting resolution. This model may be used in the future to provide new insights into the impacts of dust on regional and global climate systems. Key Points: A modeling framework of atmospheric dust with the capability of global variable‐resolution simulation is introduced and evaluatedExperiments with regional refinement produce less dust emissions and mass loading and smaller dry deposition due to weaker surface windRefinement at convection‐permitting resolution simulates stronger wet scavenging and less dust mass compared to coarse resolution [ABSTRACT FROM AUTHOR]