Thermohydraulic behavior in spent fuel pool is quite important in evaluating safety of a nuclear reactor under accidental conditions. When the liquid level of spent fuel pool decreases, fuel rods are exposed, heated up and finally failed. In order to avoid overheating of fuel rods, spray cooling is planned. Spay water is expected to enter rod bundle and cool down fuel rod. Therefore, quantity of spray water flowing into rod bundle has to be evaluated. A series of experiments were carried out for this phenomenon. The results showed that the water flowing into rod bundles is objected to the flooding and correlated by flooding correlations. However, the parameters of flooding correlations depended upon spray water flow rate and showed higher values compared with previous correlations.