The phase diagram of the ternary system NaCl-FeCl3 -H2 O was determined at four different temperatures (5, 15, 30 and 50C) by conductometry and thermal method. The experimental results show that in the temperature range 5 to 30C, only NaCl and FeCl3 6H2 O were present as solid phases. For the 50C isotherm, we have observed the crystallization fields of the NaCl and FeCl3 2,5H2 O.