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<em>Artemisia</em>, along with Chenopodiaceae is the dominant component growing in the desert and grassland of the Northern Hemisphere. The Chenopodiaceae/<em>Artemisia</em> (C/A) pollen ratio is a traditional bio-indicator to evaluate environmental aridity prior to meteorological records. However, when applying the C/A ratio from the original point in the Middle East to other regions, the validity was questioned. Compared with Chenopodiaceae pollen, which is inversely proportional to precipitation, <em>Artemisia</em> pollen with its diverse habitats is probably responsible for this uncertainty. Here we provide the <em>Artemisia</em> pollen morphological datasets covering 36 species from 9 clades and 3 outgroups under a phylogenetic framework to ensure maximum variation coverage and their source plant habitat ranges. The new pollen classification with a key to the pollen types of <em>Artemisia</em> was established by hierarchical cluster analysis. The <em>Artemisia</em> pollen classification (1) improves the resolution of bio-indicators in deep-time environmental assessment; (2) reveals that the diverse habitats colonized by <em>Artemisia</em> could be responsible for the uncertainty of the C/A pollen ratio in different regions; (3) changes the traditional concept of <em>Artemisia</em> being restricted to arid and semi-arid environments. We hope to establish an open dataset that welcomes new <em>Artemisia</em> data from all over the world in the future for better serving the global paleoenvironment assessment and refined reconstruction of paleovegetation.