The boiling heat transfer was experimentally investigated for the FC-77 sprays impacting a square heated test surface in a downward direction. Full cone spray nozzles were employed for the spray cooling experiment, and experiments were made under the test conditions of $Q=3.32{ imes}10^{-6}{sim}2.30{ imes}10^{-5};m^3/s$, ${Delta}T_{sub}=20{sim}70^{circ}C$. Also, heat transfer measurements were made using the copper block of $10{ imes}10;mm^2$ test area heated by nine cartridge heater. From the experimental results, correlation between the Nusselt number and Reynolds number based on droplet-flow-rate was developed. The correlation shows good predictions with ${pm}30%$ error for FC-77.