Abstract: According to the occurrence possibility of AC corrosion prediction, domestic assessment code relies on AC potential, while European code depends on AC density, the both of which obeys corresponding standards. Taking a specific pipeline as an example, according to AC potential, AC density, protection potential and protection current density described in domestic and foreign standards, a series of testing and calculations are carried out. By comparing the practicality of two assessment codes, it is proved that applying AC density as the assessment index is available with higher precision for AC corrosion assessment, and the limitation of traditional code which specified-850 mV(CSE) as the protection potential under the conditions of AC interference.