The relationship between processing parameters and microstructures of as-deposited thin titanium dioxide (TiO2) on silicon nitride (Si 3N4) substrate was investigated for pulsed-pressure metalorganic chemical vapor deposition (PP-MOCVD). Titanium tetra-isopropoxide (TTIP) dissolved in toluene was the precursor. The processing parameters investigated were a range of base pressures from 50 to 200 Pa and relaxation time of 0, 2.5, 5 and 10 sec. The deposition temperature, precursor concentration and injection volume were kept constant at 450°C, 0.015 M and 50 μl, respectively. The deposited films were analyzed using SEM, EDS, AFM, and XRD. The films have columnar growth anatase phase with the maximum growth rate of 3.0 nm/pulse. The grain sizes were between 59 and 236 nm and the maximum roughness was 5.75 nm. Growth rate and surface roughness was not affected by base pressure, but decreased with increased relaxation time. Grain size increased with base pressure and decreased with increased relaxation time.