The natural draft wet cooling tower will produce noise under normal operating conditions. With the increase of the scale of cooling towers in nuclear power plants and the increasingly strict requirements of environmental protection departments, the noise pollution of cooling towers (especially high level water collecting cooling towers) is becoming a new problem to be solved urgently in the field of nuclear power. Taking 3 units of a nuclear power plant in China as the research objects, the noise generation mechanism, noise pollution prediction and noise protection measures of the high level water collecting cooling tower and the usual cooling tower planned for the plant were studied. The predicted result shows that the impact of superimposed noise of two high level water collecting cooling towers and one usual cooling tower on the plant boundary cannot meet the requirements of Class 3 standards of the “Industrial Enterprise Plant Boundary Environmental Noise Emission Standard”. Noise reduction measures should be taken to make the plant boundary noise reach the standard. Through the analysis and comparison of various common noise reduction measures (such as sound insulation barrier, muffler, etc.), the recommended noise reduction scheme of the cooling tower in this project is to set sound insulation barriers near the plant boundary. The research results can provide systematic technical support for noise prediction and noise protection scheme design of natural draft wet cooling towers in nuclear power plant.