Abstract: Objective Waterlogging tolerance of seed germination stage and seedling stage in cowpea（Vigna unguiculata ）were compared，to guide the practice of seeds sowing. Methods The germination cowpea seeds and cowpea seedlings were soaked in water with different time（12，24，36，48，60，72 h），and their responses to hypoxia stress were studied. Results （1）As the flooding time prolonged，the germination of seed decreased. When the cowpea in germination stage was flooded over 36 h，the seedling rate was zero，but when the cowpea in seedling stage was flooded less than 72 h，no seedling death was observed；（2）Under flooding stress，the growth of cowpea seedlings was inhibited，and the damage of root was the most serious. Conclusion The wet resistant ability of cowpea in seedling stage was stronger than that in germination stage. The waterlogging in germination stage influence the germination and cause rotting away of seeds，it is important to choose the seeding enviroment and time.

Key words: cowpea, waterlogging tolerance, germination stage, seedling stage