摘要The flower is an evolutionary innovation in angio-sperms that drives the evolution of biodiversity. The carpel is integral to a flower and develops into fruits after fertilization, while the perianth, con-sisting of the calyx and corolla, is decorative to facilitate pollination and protect the internal or-gans, including the carpels and stamens. There-fore, the nature of flower origin is carpel and stamen origin, which represents one of the greatest and fundamental unresolved issues in plant evolutionary biology. Here, we briefly sum-marize the main progress and key genes identified for understanding floral development, focusing on the origin and development of the carpels. Floral ABC models have played pioneering roles in elu-cidating flower development, but remain in-sufficient for resolving flower and carpel origin. The genetic basis for carpel origin and subsequent di-versification leading to fruit diversity also remains elusive. Based on current research progress and technological advances, simplified floral models and integrative evolutionary-developmental (evo-devo) strategies are proposed for elucidating the genetics of carpel origin and fruit evolution. Step-wise birth of a few master regulatory genes and subsequent functional diversification might play a pivotal role in these evolutionary processes. Among the identified transcription factors, AG-AMOUS (AG) and CRABS CLAW (CRC) may be the two core regulatory genes for carpel origin as they determine carpel organ identity, determinacy, and functionality. Therefore, a comparative identi-fication of their protein–protein interactions and downstream target genes between flowering and non-flowering plants from an evo-devo perspective may be primary projects for elucidating carpel origin and development.