Nanocrystalline TiO2 thin films have been successfully synthesized by controlled precipitation route. These films are further annealed at 623 K for 2 h. The change in structural, morphological, optical, and wettability properties are studied by means of X-ray diffraction (XRD), Fourier transform infrared spectrum (FTIR), scanning electron microscopy (SEM), optical absorption, and contact angle measurement. From the XRD pattern it is clear that the as-grown TiO2 films are amorphous in nature which becomes polycrystalline after annealing. The FTIR study reveals the formation of TiO2 compound. Scanning electron micrographs shows that the as-grown TiO2 film consists of agglomerated nanograins well covered to the substrate surface which gets converted into vertical nanorods after annealing. As-deposited and annealed TiO2 films showed hydrophilic behavior as water contact angles were 24A degrees and 32A degrees, respectively. The optical absorption study reveals the small red shift due to annealing and attributed to grain size. The annealed TiO2 film showed conversion efficiency of 0.037% in photoelectrochemical cell with 1 M NaOH electrolyte.