In this research, a MADS-box gene, CCFMADS, was cloned from Calocedrus formosana. Through phylogenetic analyses and similarities of specific C-terminal motifs, this gene was categorized into C-function lineages belonging to the AGAMOUS family. The CCFMADS-specific C-terminal motif shared high similarity with C and D-functional types of genes, and showed little divergence with other gymnosperms. In addition, transgenic Arabidopsis thaliana was used to evaluate the function of the CCFMADS gene. All sense transgenic plants displayed abnormal vegetative growth, such as smaller and curling leaves. According to a Northern blot analysis of CCFMADS expression in different months in C. formosana, we assumed that the CCFMADS gene may play an important role at the stage when vegetative buds convert to reproductive buds.