This paper presents a study on the performances of distance relays setting in 400 kV in Eastern Algerian transmission networks at Sonelgaz Group (Algerian company of Electrical and Gas) compensated by shunt Flexible AC Transmission System (FACTS). The facts are used for controlling transmission voltage, power flow, reactive power, and damping of power system oscillations in high power transfer levels. The effects of SVC devices i.e. Thyristor Controlled Reactor (TCR) and the Thyristor Switched Capacitors (TSC) insertion, on the total impedance of a transmission line protected by MHO distance relay are investigated. The modified setting zones protections for three forward zones (Z₁, Z₂ and Z₃) have been calculated in order to improve the performances of distance relay protection and prevent circuit breaker nuisance tripping.