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Aerial seed bank has been found in the arid dune ecosystem. However, the relationship of aerial seed bank to sand mobility intensity is unknown. The adaptation of aerial seed bank to sand mobility was analyzed in four Artemisia species dominating at different habitats in northeastern Inner Mongolia, China. The four species, Artemisia gmelinii, A. frigida, A. halodendron and A. wudanica, are an interdune lowland, stabilized dune, semi-stabilized dune and active dune species, respectively. Seed (achene and capitulum) persistence on the parent plants, the supplement for the soil seed bank, the maintenance of seed viability, and the effect of burial depth on seedling emergence of these four species were studied. Dispersal delay differed interspecifically responding to sand mobility intensity: maximal dispersal was in the following May after maturation for A. wudanica, in the following April after maturation for A. halodendron, and in November of the year of seed maturation for A. frigida and A. gmelinii. The maximal supplement to the soil seed bank for A. wudanica and A. halodendron occurred in the following May and March, respectively. The viability of achenes in aerial seed bank of A. wudanica and A. halodendron maintained at 79.5 and 79.6% until the following May after maturation. This study indicated that aerial seed bank in the sand dune ecosystem functions to postpone seed dispersal until the end of windy season and the start of growing season, and therefore is a mechanism for psammophyte to adapt to sand mobility.