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The phytochrome-interacting factors (PIFs) proteins belong to the subfamily of basic helix–loop–helix (bHLH) transcription factors and play important roles in chloroplast development and chlorophyll biosynthesis. Currently, knowledge about the <i>PIF</i> gene family in <i>Camellia sinensis</i> remains very limited. In this study, seven PIF members were identified in the <i>C. sinensis</i> genome and named based on homology with <i>AtPIF</i> genes in <i>Arabidopsis thaliana.</i> All <i>C. sinensis</i> PIF (CsPIF) proteins have both the conserved active PHYB binding (APB) and bHLH domains. Phylogenetic analysis revealed that CsPIFs were clustered into four groups—PIF1, PIF3, PIF7, and PIF8—and most CsPIFs were clustered in pairs with their corresponding orthologs in <i>Populus tremula</i>. <i>CsPIF</i> members in the same group tended to display uniform or similar exon–intron distribution patterns and motif compositions. <i>CsPIF</i> genes were differentially expressed in <i>C. sinensis</i> with various leaf colors and strongly correlated with the expression of genes involved in the chlorophyll metabolism pathway. Promoter analysis of structural genes related to chlorophyll metabolism found DNA-binding sites of PIFs were abundant in the promoter regions. Protein–protein interaction networks of CsPIFs demonstrated a close association with phytochrome, PIF4, HY5, TOC1, COP1, and PTAC12 proteins. Additionally, subcellular localization and transcriptional activity analysis suggested that CsPIF3b was nuclear localized protein and possessed transcriptional activity. We also found that CsPIF3b could activate the transcription of <i>CsHEMA</i> and <i>CsPOR</i> in <i>Nicotiana benthamiana</i> leaves. This work provides comprehensive research of CsPIFs and would be helpful to further promote the regulation mechanism of PIF on chlorophyll metabolism in <i>C. sinensis</i>.