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<i>FLOWERING LOCUS T</i> (<i>FT</i>), belonging to the <i>FT</i>/<i>TFL1</i> gene family, is an important gene regulating the flowering transition and inflorescence architecture during plant development. Given its importance to plant adaptation and crop improvement, <i>FT</i> has been extensively studied in related plant research; however, the specific role and underlying molecular mechanisms of <i>FT</i> in the continuous flowering of perennial plants remains elusive. Here, we isolated and characterized homologous <i>FT</i> genes from two <i>Camellia</i> species with different flowering-period phenotypes: <i>CaFT</i> was isolated from <i>Camellia azalea</i>, a precious species blooming in summer and flowering throughout the year, and <i>CjFT</i> was isolated from <i>C. japonica</i>, which blooms in winter and spring. The major difference in the genes between the two species was an additional five-amino acid repeat sequence in <i>C. japonica</i>. <i>FT</i> showed high expression levels in the leaves in both species from January to August, especially in April for <i>C. japonica</i> and in May for <i>C. azalea</i>. <i>CaFT</i> was expressed throughout the year in <i>C. azalea</i>, whereas <i>CjFT</i> was not expressed from September to December in <i>C. japonica</i>. The expression levels of <i>FT</i> in the floral buds were generally higher than those in the leaves. Overexpression of <i>CaFT</i> and <i>CjFT</i> in <i>Arabidopsis</i> indicated that both genes can activate downstream genes to promote flowering. Transgenic callus tissue was obtained by introducing the two genes into <i>C. azalea</i> through <i>Agrobacterium</i>-mediated transformation. Transcriptome and quantitative real-time polymerase chain reaction analyses indicated that both florigen <i>FT</i> genes promoted the expression of downstream genes such as <i>AP1</i>, <i>FUL</i>, and <i>SEP3</i>, and slightly up-regulated the expression of upstream genes such as <i>CO</i> and <i>GI</i>. The above results indicated that <i>CaFT</i> and <i>CjFT</i> played a role in promoting flowering in both camellia species. The expression pattern of <i>CaFT</i> in leaves suggested that, compared to <i>CjFT, CaFT</i> may be related to the annual flowering of <i>C. azalea</i>.