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Trehalose and some members of the <i>trehalose 6-phosphate synthase</i> (<i>TPS</i>) gene family play important roles in response to abiotic stress in plants. However, no studies investigating the <i>TPS</i> gene in rose have been reported. In this study, the trehalose content in the stems and roots of <i>Ros</i><i>a chinensis</i> was significantly increased under heat stress, and nine <i>TPS</i> family members were identified from the genome of <i>R. chinensis</i>. The <i>R. chinensis TPS</i> (<i>RcTPS</i>) family members could be divided into two subfamilies based on the structure and phylogenetic analysis. In this study, we found that segmental duplications contributed to the expansion of the <i>RcTPS</i> gene family, and the type II subfamily gene pairs <i>RcTPS9</i>–<i>RcTPS10</i> and <i>RcTPS7a</i>–<i>RcTPS7b</i> were created by segmental duplication events. The type I subfamily <i>RcTPS</i> members contained 17 exons in the protein-coding region, whereas type II subfamily members only had 3 or 4 exons. Most <i>cis</i>-acting elements in the promoters of <i>RcTPS</i> members were related to plant hormones, especially ABA hormones. A phylogenetic tree of 78 TPS homologous amino acids from <i>R</i><i>. chinensis</i> and another 7 species was constructed, which could be divided into 5 clades, and purity selection was observed to be the dominant evolutionary selection pressure. Under heat stress, except for <i>RcTPS1b</i>, the other eight <i>RcTPS</i> members were upregulated in the roots, stems, orleaves. The type II subfamily members <i>RcTPS7a</i> and <i>RcTPS7b</i> showed significantly high expression patterns in response to heat stress in all three tissues. Our findings indicate that <i>RcTPS7a</i> and <i>RcTPS7b</i> may play important roles in the heat tolerance of <i>R. chinensis</i> and are helpful for future functional studies of the two <i>RcTPS</i> members during heat stress.