The purpose of this investigation is to study heat transfer characteristics at a stagnation point on a flat plate caused by upward impinging water jet. At the stagnation point, heat transfer results by impinging water jet are being compared with the ones with supplementary water. Optimum supplementary water quantity are supplied in order to improve the effect of heat transfer for each nozzle-to-plate distance. As the nozzle outlet velocity increases, the heat transfer coefficient at stagnation point consequently increases. Changing the nozzle-to-plate distance, growth rate of heat transfer also varies accordingly. This optimum range of Reynolds number is obtained to improve heat transfer effect.