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Heat shock transcription factors (Hsfs) are key regulators in plant heat stress response, and therefore, they play vital roles in signal transduction pathways in response to environmental stresses, as well as in plant growth and development. <i>Canavalia rosea</i> (Sw.) DC. is an extremophile halophyte with good adaptability to high temperature and salt-drought tolerance, and it can be used as a pioneer species for ecological reconstruction on tropical coral islands. To date, very little is known regarding the functions of <i>Hsf</i>s in the adaptation mechanisms of plant species with specialized habitats, especially in tropical leguminous halophytes. In this study, a genome-wide analysis was performed to identify all the <i>Hsf</i>s in <i>C. rosea</i> based on whole-genome sequencing information. The chromosomal location, protein domain or motif organization, and phylogenetic relationships of 28 <i>CrHsf</i>s were analyzed. Promoter analyses indicated that the expression levels of different <i>CrHsf</i>s were precisely regulated. The expression patterns also revealed clear transcriptional changes among different <i>C. rosea</i> tissues, indicating that the regulation of <i>CrHsf</i> expression varied among organs in a developmental or tissue-specific manner. Furthermore, the expression levels of most <i>CrHsf</i>s in response to environmental conditions or abiotic stresses also implied a possible positive regulatory role of this gene family under abiotic stresses, and suggested roles in adaptation to specialized habitats such as tropical coral islands. In addition, some <i>CrHsfA</i>s were cloned and their possible roles in abiotic stress tolerance were functionally characterized using a yeast expression system. The <i>CrHsfA</i>s significantly enhanced yeast survival under thermal and oxidative stress challenges. Our results contribute to a better understanding of the plant <i>Hsf</i> gene family and provide a basis for further study of <i>CrHsf</i> functions in environmental thermotolerance. Our results also provide valuable information on the evolutionary relationships among <i>CrHsf</i> genes and the functional characteristics of the gene family. These findings are beneficial for further research on the natural ecological adaptability of <i>C. rosea</i> to tropical environments.