Abstract: In nuclear power facilities, steam generators (SG) can undergo secondary water chemical treatment using polyacrylic acid (PAA) to lessen the deposition of corrosion products. The production of small molecule organic acids by PAA's breakdown at high temperatures, could hasten the corrosion of SG components' crevices. Using sheet-like and tubular crevice corrosion specimens, the impact of PAA on the crevice corrosion behavior of 690TT alloy pipes was examined in a water environment that simulated SG high temperatures and high pressures environment. According to the findings, the corrosion rates of the two kinds of crevice corrosion samples dropped by 38% and 22%, respectively, following the addition of 100 mg/L PAA. The 690TT alloy crevice corrosion was not accelerated by the use of PAA.