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Plant NAPDH oxidase (<i>NOX</i>) gene family members are critical producers of ROS and play crucial roles in plant signaling, development, and stress responses. <i>Opisthopappus taihangensis</i> is a pivotal wild genetic resource in Asteraceae. To date, little knowledge exists about the functions of <i>NOXs</i> in <i>O. taihangensis</i>. In this study, seven typical <i>NOXs</i> and seven ferric reduction oxidases (<i>FROs</i>) were identified in <i>O. taihangensis</i>. Dispersed duplication might play a critical role in the expansion of the <i>NOX/FRO</i> gene family in <i>O. taihangensis</i>, and most of the <i>NOX/FRO</i> homologous pairs have undergone purifying selection. Although the results of the collinearity analysis show that these genes were relatively conserved, the gain and loss of members in this gene family occurred frequently during the evolution of Asteraceae. Phylogenetic analysis indicated that the <i>FROs</i> are relatively ancient, and the earliest diverged branch was revealed by the maximum likelihood (ML) tree. The Asteraceae <i>NOXs</i> were divided into six subgroups according to their relationship with <i>Arabidopsis</i> and rice members. The transcriptome profile unveiled tissue-specific expression patterns and complex response modes under drought and salt stresses. <i>OtNOX6</i> and <i>OtNOX7</i> could be recognized as important candidates to respond to drought and salt stress. Our results provide clues and references for further in-depth exploration of <i>NOX/FRO</i> function in <i>O. taihangensis</i> and other horticulture plants.