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ZF-HD transcription factors, which are unique to land plants, are involved in the regulation of abiotic stress response and related signaling pathways, and play a crucial role in plant growth and development. <i>Dendrobium</i> is one of the largest genera of orchids, with a high ornamental and ecological value. However, the specific functions of the <i>ZF-HD</i>s in <i>Dendrobium</i> remain unknown. In this study, we identified a total of 53 <i>ZF-HD</i>s from <i>D. chrysotoxum</i> (17), <i>D. catenatum</i> (23), and <i>D. huoshanense</i> (13), and analyzed their physicochemical properties, phylogenetic relationships, chromosomal locations, protein structures, conserved motifs, and expression patterns. The phylogenetic relationships revealed that 53 <i>ZF-HD</i>s were classified into six subfamilies (ZHDI–V and MIF), and all ZF-HD proteins contained motif 1 and motif 4 conserved domains, while a minority of these proteins had exons. The analysis of <i>cis</i>-elements in the promoters of <i>ZF-HD</i>s from three <i>Dendrobium</i> species showed that growth- and development-related elements were the most prevalent, followed by hormone response and abiotic stress response elements. Through collinearity analysis, 14 <i>DchZF-HD</i>s were found to be collinear with <i>DhuZF-HD</i>s, and 12 <i>DchZF-HD</i>s were found to be collinear with <i>DcaZF-HD</i>s. Furthermore, RT-qPCR analysis revealed that <i>DchZF-HD</i>s play a regulatory role in the development of lateral organs during the flowering process. The results indicated that <i>DchZHD2</i> plays a role in the unpigmented bud stage, while <i>DchMIF8</i> and <i>DchZHD16</i> play significant roles during the pigmented bud and initial bloom stages. Hence, this study provides a crucial basis for further exploring <i>ZF-HDs</i> functions in regulating the floral organs of orchids.