Abstract: The diversity and dynamics of arthropods on Seriphidium terraealbae and Calligonum leucocladum in southern marginal zone of Gurbanggut Desert was explored in order to protect S. terraealbae and C. leucocladum and provide reference for rationally using arthropods in ecotone. The fixedpoint sampling method was used once a week in this research. The habitats were divided into desert and ecotone. A total of 677 specimens were collected, which belonged to 2 classes, 10 orders and 22 families. The species richness index and biodiversity index were significantly greater in ecotone than in desert. The dominance index was opposite. The individual number of natural enemy insects was significantly higher in ecotone than in desert. The main herbivore groups were Fulgoroidea, Cicadellidae, Acridoidea, Miridae, Curculionidae, and Aphididae; the main natural enemy insects groups were Chalcidoidea, Braconidae, Ichneumonidae, Chrysopidae, and Araneida. The individual number of herbivore reached two peaks in middle of May and early July; the number of natural enemy insects reached two peaks behind the herbivore in late May and middle of July. The natural enemy insects were rich for S. terraealbae and C. leucocladum in ecotone, and most of them could fly and transfer to farmland and desert ecosystems as supplement, being important in the ecological significance. Accordingly, S. terraealbae and C. leucocladum should be protected from overgrazing in ecotone.