In order to conduct the low-voltage power line carrier communication on electromagnetic compatibility impact study of residual current operated protective device conveniently in the laboratory,the testing system of low-voltage power line carrier communication on electromagnetic compatibility for residual current operated protective device is established and the electromagnetic compatibility testing method as well as testing program of residual current operated protective device,which is injected analog carrier signal in two kinds of forms:differential mode and common mode, is proposed in this paper,proving that the reasonableness of this testing system.This testing systm and testing method have important practical value.