Operational experiences indicate that when a high resistance ground fault occurs on one of two parallel double-circuit lines under the strong-magnetic and weak-current operation condition， the pilot zero sequence directional protection of the non-fault line may mal-function while the pilot negative sequence directional protection will not. If a pilot negative sequence directional protection is used to replace the zero sequence one， the mal-function caused by high resistance ground faults can be avoided. A new pilot negative sequence directional protection scheme is also presented， which combines a negative sequence reactance relay， negative sequence current and voltage blocking， and a short time delay. The scheme can avoid mal-function of the protection on the non-fault line and isolate the faulty line reliably.