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Phosphorus transporter (<i>PHT</i>) genes encode H₂PO^4&#8722;/H⁺ co-transporters that absorb and transport inorganic nutrient elements required for plant development and growth and protect plants from heavy metal stress. However, little is known about the roles of <i>PHTs</i> in <i>Brassica</i> compared to <i>Arabidopsis thaliana</i>. In this study, we identified and extensively analyzed 336 PHTs from three diploid (<i>B. rapa, B. oleracea,</i> and <i>B. nigra</i>) and two allotetraploid (<i>B. juncea</i> and <i>B. napus</i>) <i>Brassica</i> species. We categorized the <i>PHTs</i> into five phylogenetic clusters (<i>PHT1</i>&#8722;<i>PHT5</i>), including 201 <i>PHT1</i> homologs, 15 <i>PHT2</i> homologs, 40 <i>PHT3</i> homologs, 54 <i>PHT4</i> homologs, and 26 <i>PHT5</i> homologs, which are unevenly distributed on the corresponding chromosomes of the five <i>Brassica</i> species. All <i>PHT</i> family genes from <i>Brassica</i> are more closely related to Arabidopsis <i>PHTs</i> in the same vs. other clusters, suggesting they are highly conserved and have similar functions. Duplication and synteny analysis revealed that segmental and tandem duplications led to the expansion of the <i>PHT</i> gene family during the process of polyploidization and that members of this family have undergone purifying selection during evolution based on Ka/Ks values. Finally, we explored the expression profiles of <i>BnaPHT</i> family genes in specific tissues, at various developmental stages, and under heavy metal stress via RNA-seq analysis and qRT-PCR. <i>BnaPHTs</i> that were induced by heavy metal treatment might mediate the response of rapeseed to this important stress. This study represents the first genome-wide analysis of <i>PHT</i> family genes in <i>Brassica</i> species. Our findings improve our understanding of <i>PHT</i> family genes and provide a basis for further studies of <i>BnaPHTs</i> in plant tolerance to heavy metal stress.