摘要Cultivated hawthorn (Crataegus pinnatifida var. major) is an important medicinal and edible plant with a long history of use for health protection in China. Herein, we provide a de novo chromosome-level genome sequence of the hawthorn cultivar"Qiu Jinxing."We assembled an 823.41 Mb genome encoding 40571 genes and further anchored the 779.24 Mb sequence into 17 pseudo-chromosomes, which account for 94.64％ of the assembled ge-nome. Phylogenomic analyses revealed that culti-vated hawthorn diverged from other species within the Maleae (apple tribe) at approximately 35.4 Mya. Notably, genes involved in the flavonoid and triterpenoid biosynthetic pathways have been sig-nificantly amplified in the hawthorn genome. In ad-dition, our results indicated that the Maleae share a unique ancient tetraploidization event; however, no recent independent whole-genome duplication event was specifically detected in hawthorn. The amplification of non-specific long terminal repeat retrotransposons contributed the most to the ex-pansion of the hawthorn genome. Furthermore, we identified two paleo-sub-genomes in extant species of Maleae and found that these two sub-genomes showed different rearrangement mechanisms. We also reconstructed the ancestral chromosomes of Rosaceae and discussed two possible paleo-polyploid origin patterns (autopolyploidization or al-lopolyploidization) of Maleae. Overall, our study provides an improved context for understanding the evolution of Maleae species, and this new high-quality reference genome provides a useful resource for the horticultural improvement of hawthorn.