BaTiO3 powder was synthesized by a solid-state reaction using BaCO3 and TiO2. Different calcination temperatures (800℃, 850℃, 900℃, and 950℃) were set to investigate their effects on the properties of BaTiO3 powder. The synthesized BaTiO3 phase was confirmed to be a single phase by XRD, and the tetragonality (c/a) and crystallite size were calculated. Thereafter, each calcinated BaTiO3 was sintered at five different sintering temperatures (1,100℃, 1,150℃, 1,200℃, 1,250℃, and 1,300℃), and the tetragonality, density, porosity, dielectric constant, and grain size were measured. As the calcination temperature increased, the tetragonality and crystallite size also increased, to 1.008 and 66 nm, respectively, at 950℃. Moreover, most pellets showed increased density, dielectric constant, and tetragonality as the sintering temperature increased up to 1,250℃; the same parameters slightly decreased at 1,300℃. It is noteworthy that the tetragonality of BaTiO3 at 1,250℃ exhibits a very high c/a value of 1.0084. In addition, the grain size and dielectric constant measured near the Curie temperature increased as the sintering temperature increased.