T22 low alloy steel is represented as one of the best alloy using to production oil pipe, patrol valves, high temperature applications. This alloy has good mechanical properties, a satisfaction corrosion resistance and acceptable thermal conductivity at nature conditions. At high pressure applications with rapid flow of a fluid stream, T22 alloy is suffered severe degradation or corrosion. Though in an attempt to reduce the damage caused by corrosion, it has been resorting to the addition of La3O2, that is working on created a composition phase and a protective layer of corrosion. Where they were mixing alloy elements powders with different amount of La3O2 nanoparticles. mixed powder was prepared by powder metallurgy PM method and using a press at compression strength 175 MPa in mold steel cylindrical shape die, mold diameter is 20 mm and a height of 100 mm, sintering process has been done at a temperature 1200 °C and using Argon gas as inert gas. X-ray diffraction examination was used to identify the phases formed and microscopic structure of samples after sintering was also examined using scanning electron microscope, Archimedes method was examined to measured density and porosity of sintered samples. The examination of erosion corrosion has used a private system and thus adopted the corrosive sea water as a medium. Erosion corrosion test results showed clearly increased corrosion resistance with increasing of La3O2 amount, due to existence resistance to corrosion phase. 10 vol.% of La3O2 nanoparticles is the best nanoadditives amount which support a good resistance to erosion corrosion.