The results of studies of the noise of power transformers at the enterprises of the machine-building complex are presented in this paper. The causes of the noise of power transformers are identified, the analysis is made, and the main design indicators affected the increase in the sound power level of high-voltage converters are determined. Based on the analysis of design indicators, organizational and technical measures are proposed for improving reliability and accident-free operation of power transformers, as well as reduction of the noise level of power transformers.