Abstract: To study the way of breaking the dormancy of cowpea seeds,‘Tianchang No.1’was used as material, the hydro-priming was conducted with 20℃ water and 6 different soaking time, and then the seeds were dried again. The swelling rate, water absorption speed and germination rate of cowpea seeds were analyzed. The results showed that along with the prolonging of hydro-priming within 24 h, the swelling rate presented a fast-slow-fast pattern, the water absorption rate and germination rate increased gradually. The germination rates in 24 h and 12 h treatment were close, 85% and 88%, respectively, indicating that the newly harvested cowpea seeds could meet the production demand under hydro-priming at 20℃ for 12 h.