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In plants, the HAK (high-affinity K⁺)/KUP (K⁺ uptake)/KT (K⁺ transporter) family represents a large group of potassium transporters that play important roles in plant growth and environmental adaptation. Although <i>HAK/KUP/KT</i> genes have been extensively investigated in many plant species, they remain uncharacterized in wheat, especially those involved in the response to environmental stresses. In this study, 56 wheat <i>HAK/KUP/KT</i> (hereafter called <i>TaHAK</i>s) genes were identified by a genome-wide search using recently released wheat genomic data. Phylogenetic analysis grouped these genes into four clusters (&#921;, II, III, IV), containing 22, 19, 7 and 8 genes, respectively. Chromosomal distribution, gene structure, and conserved motif analyses of the 56 <i>TaHAK</i> genes were subsequently performed. In silico RNA-seq data analysis revealed that <i>TaHAK</i>s from clusters II and III are constitutively expressed in various wheat tissues, while most genes from clusters I and IV have very low expression levels in the examined tissues at different developmental stages. qRT-PCR analysis showed that expression levels of <i>TaHAK</i> genes in wheat seedlings were significantly up- or downregulated when seedlings were exposed to K⁺ deficiency, high salinity, or dehydration. Furthermore, we functionally characterized <i>TaHAK1b-2BL</i> and showed that it facilitates K⁺ transport in yeast. Collectively, these results provide valuable information for further functional studies of <i>TaHAKs</i>, and contribute to a better understanding of the molecular basis of wheat development and stress tolerance.