Abstract: Systematically investigated here in the article are the intergranular corrosion behaviors of the 304 stainless steel tubular product as going through different processing technologies. Also comparatively analyzed are the influences on the microstructure and corrosion resistance of the material by such process steps as tube cutting and bending,water expanding,heat treatment and polishing,etc.,and then it is revealed that in case of the macro size,i.e.,10~200 magnification,none of the process specimen presents any intergranular corrosion,being up to the requirement of applicable specification;while in case of the micro size,i. e.,500 magnification,the post-bending heat treatment specimen presents slight intergranular corrosion;the corrosion is getting more and more serious with the water-expanding process,and even after the water-expanding plus the heat treatment,the corrosion still remains obviously;the polishing process leads to the most serious intergranular corrosion;the analysis of the deformation structure shows that the deformation structure in the external layer of the elbow as being flattened is easy to crack;however heat treatment can eliminate such structure,and get the cracking trend improved. It is finally recommended to improve the polishing process parameters,and add the passivation treatment so as to remarkably enhance the corrosion resistance of the tubular product.