The Curie point (T C) of BaTiO3 was earlier reported to be 120° C and has been recently believed to be 130° C. Some experiments have been performed here to reconfirm the T C. Firing conditions used for preparing BaTiO3 were examined first with the use of pure BaCO3 or Ba(NO3)2 and TiO2. The x-dependence of T C in (BaO)1- x (TiO2)1+ x solid solution was measured. Data were scattered and suffered from individual variations. According to probability considerations, T C of BaTiO3 was evaluated from the intercept at x=0. On the other hand, composition dependence of T C in some related solid solution systems, (Ba1- y Pb y )TiO3. (Ba1- y Sr y )TiO3 and (BaTiO3)1- y (KF) y , was examined and the T C of BaTiO3 was estimated by extrapolation toward the limit y→0. In conclusion, the Curie point of BaTiO3 is determined as 123.0±0.6° C.