Through the test of 27 groups of specimens, the influence lawoncompressive strength and expansionundersea salt corrosionbytype of cement, fly ash substitute rate of cement, fly ash substitute rate of fine aggregate, water-binder ratio, type of fine aggregate, and immersion methodwere analyzed. The corrosion resistance of reinforced concrete under sea water attack was also studied in this research. The experimental results indicate that the influence of various factors onthe compressive strength is correlative, and the interaction effects of the type of cement and type of fine aggregate, type of cement and immersion methodon the compressive strength are correlative; fly ash substitute rate of fine aggregate, water-binderratio, type of fine aggregate and immersion wereall had significant effects on the expansionat each age. The immersion methodhad the most significant effect on the expansion. The type of fine aggregate has a significant effect on all tests, but other more correlative factors can be used to improve the deterioration of cement mortar caused by sea sand. Replacement of 10% or 20% aggregate by fly ash gives no apparent improvement in preventing the expansionof cement mortar inseawater exposure. The concrete test results indicate that no serious detrimental effect was found for the corrosion inhibitor in reinforcedconcrete.