Abstract: Gene duplication and diversification can provide the raw material for discovering morphological changes in organisms.The MADS-box genes encoding a family of transcription factors have undergone extensive gene duplication events and subsequent functional divergence during evolution. In flowering plants, MADS-box genes control diverse developmental processes in organs ranging from roots to flowers and fruit development. Studies on the evolutionary history of the MADS-box gene family have highlighted the dynamic fates of the duplicate genes and can provide evidence to better understand the mechanisms behind the evolution of plant morphology. This paper reviews the progress of gene duplication and subsequent functional diversification in the MADS-box gene family.