Abstract: High back pressure heating unit is more and more used in heating power plant in winter because of its good economic benefits. Due to the improper control of pH value, hardness and other indexes during the operation of the heating circulating water system of high back pressure units, and the improper lay-up protection of the network, scaling and corrosion of heaters and condensers are easy to occur. It brings great risks to the safe and stable operation of the unit during the heating period. According to the scaling and corrosion problems of the heating circulating water system in the high back pressure unit of the power plant, the causes are analyzed from the operation data. The treatment measures of water quality control and lay-up protection are put forward to ensure the safe, economic and stable operation of the heating network system during the heating period.