MTiO3 (M = Ca, Ni, and Zn) nanocrystals were prepared via a facile ethylene glycol-mediated synthesis route followed by calcination in air. The structures and morphologies of nanocrystals were characterized by x-ray diffraction, Raman spectroscopy, transmission electron microscopy, and scanning electron microscopy. The results indicated that CaTiO3 and NiTiO3 are orthorhombic phase, while the ZnTiO3 is orthorhombic phase. The activity of the CaTiO3 nanocrystals for water splitting into H2 was obviously higher than those of the NiTiO3 and ZnTiO3 nanocrystals, which could be attributed to the more negative conduction band position of CaTiO3 than NiTiO3 and ZnTiO3. The Brunauer–Emmett–Teller system-based surface areas of samples are 19.03, 21.13, and 4.17 m2/g for CaTiO3, NiTiO3, and ZnTiO3 nanocrystals, respectively. In addition, the activity of the CaTiO3 nanocrystals increased with increase in the sintering temperature of samples.