Abstract: The allowable harmonic current limits injected to the common connection points are stipulated for users respectively by GB/T 14549—93 and IEEE std.519:2014. However, there are some differences between two standards in determination methods and engineering application. The harmonics national standard GB/T 14549 under revision intends to adopt the emission limits of harmonic current for single user in IEEE std.519:2014. Therefore, it is necessary to fully discuss the rationality of the methods for determining the harmonic current limits. In this paper, the limits of the harmonic current in two standards are introduced, and their determination methods are deduced and discussed respectively. Finally, the similarities and differences between them are analyzed through case study.