Abstract: The mechanism, influence factors and protection techniques of the materials corrosion in liquid PbBi eutectic are summarized in the paper. The main corrosion mechanism is: 1) the dissolution and mass transer of the composition elements of the materials in liquid PbBi eutectic; 2) the chemical reaction between the composition elements and oxygen in PbBi eutectic; 3) the intergranular boundary brittle resulting from the PbBi penetration along the intergranular boundary of the materials. The influence factors are as following:1) the temperature and the temperature differential in the system; 2) the oxygen content or oxygen part pressure in the system; 3) the chemical composition of the materials; 4) the velocity of the PbBi eutectic.The controlling and measurement of the oxygen content in PbBi eutectic is a key technique for the prevention of the materials corrosion. Moreover, the treatment and modified of the materials surface will also have a good prospect for the prevention of the materials corrosion in PbBi eutectic. 