4H-SiC asymmetrical Sate turn-off thyristors (GTO's) with 2.6 kV breakover voltage have been tested with respect to gate turn-off performance. Transient characteristics of the GTO's and pulse regime of gate turn-off processes were studied in the temperature range from 293 to 500 It. Under cathode current density of 309 A/cm(2), turn-off current gain, K(G), of 12.5 was achieved at room temperature. The value of K(G) is the highest reported for SiC GTO's. The temperature dependencies of turn-off time, pulse turned off gate current and holding current were studied.