Asian dust storms markedly affect the ecosystem, environment, ocean biogeochemical cycle, and regional climate. Numerous measurements and model simulations have been performed to investigate the sources and transport of Asian dust. However, until now, few studies have performed a comprehensive quantification of the dust budget, resulting in significant uncertainty about the characterization of dust transport, emission, and deposition. In this study, a severe dust event in East Asia that occurred from April 28 till May 3, 2011, was analyzed in terms of dust transport characteristics based on multi-satellite observations and the Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model. In particular, the dust budget of the event was quantitatively estimated using a new atmospheric reanalysis dataset, namely the second Modern-Era Retrospective Analysis for Research and Applications (MERRA-2). The multi-satellite observations and models indicated that dust events such as this are uncommon. A two-layered dust structure was found in southeast China, the lower (< 1.5 km) and elevated (> 3 km) layers of which mainly originated from the Gobi and Taklimakan Deserts, respectively. The dust budget in East Asia, as estimated from MERRA-2, revealed a high dust mass loading (5.7–6.6 Tg) between 70°E and 140°E from April 29 till May 1, with the highest daily dust loading (approximately 6.6 Tg) reported on April 30. The total dust emission was 6.3 Tg over a 6-day period (April 28–May 3), and the maximum amount (nearly 5.9 Tg) of dust was deposited on the ground in the region. The dust flux amounts horizontally transported across the longitudinal boundary of 70°E and 140°E were 1.7 and 2.8 Tg, respectively.