In this paper, the differences of intergranular corrosion test requirements using copper sulfatesulfuric acid test method in ASTM A262, NB/T 20004 and GB/T 4334 three standards were analyzed, and the conclusions were got through comparing from four aspects including specimen preparation, sensitization heat treatment, corrosion test and evaluation, it was concluded that the three standards are different, and there are no substitution among these standards. So to a certain extent, for austenitic seamless stainless steel pipe in different material systems, the intergranular corrosion test should be performed in accordance with the corresponding standard stipulated in the relative material procurement specifications.