TGA (TGACG motif binding factor) transcription factors are an important group of the bZIP transcription factor family, which have broad-spectrum resistance to plant pathogens. Rosa chinensis ‘Old Blush’ TGA family members were identified in this study, with their physicochemical properties, subcellular localization, evolutionary characteristics and expression patterns analyzed. Seven RcTGAs were identified, all containing the conserved domains of bZIP1 (cl21462) and DOG1 (pfam14144), with the amino acid size of 324 to 545 aa, the molecular weight of 36.68 to 60.17 KD, the isoelectric point of 5.52 to 8.96, and the secondary structure of mainly α-helix, all being hydrophilic proteins mainly located in the nucleus. TGAs from Rosa chinensis ‘Old Blush’, Arabidopsis thaliana, Fragaria vesca, Prunus persica, and Malus domestica were divided into six subgroups through evolutionary analysis. The qPCR test showed that the expression of RcTGA4 did not significantly change in the petals after being infected by Botrytis cinerea, and the expression of RcTGA6 decreased after the infection, whereas the expression of RcTGA1/2 increased significantly, and the expression of RcTGA3/5/7 increased first and decreased later, indicating that RcTGA1/2/3/5/7 may play an important role in the resistance to B. cinerea, and could be candidate disease-resistance gene for further research and functional analysis. After silencing the expression of RcTGA2 by VIGS, the lesion diameter in rose petals increased significantly 48 h after infection by B. cinerea, indicating that RcTGA2 may be closely related to the resistance of rose to B. cinerea.