The effects of hydration-dehydration seed treatments on germination and storage potential were studied in two cultivars of snap bean seeds (Macarrão Favorito AG-480 e Macarrão Preferido). The seed samples of each cultivar were divided into two portions and one of them was submitted to an accelerated ageing for 48 hours at 100% RH and 41°C; this portion constitued a low vigor lot. The hydration treatment was given to both portions for periods of 0, 12, 24, 36 and 48 hours. After each hydration period, the seeds were dried for 24 hours at room temperature. The evaluations done immediately after treatments and at 40 days intervals during five mounths, consisted of germination test and sand emergence The results indicated that hydration-dehydration contributed to improve performance in medium physic logical quality seed lots, but wasn?t viable in high and low vigour Iots.