This study aims to obtain titanium dioxide (TiO 2) fine particle with a narrow size distribution by one step production via flame spray pyrolysis (FSP) using LPG (liquid petroleum gas) as a fuel source. The TiO 2 particles were synthesized from the aqueous based precursor from dissolving of titanium (IV) isopropoxide to the acidic distilled water solvent. The effect of precursor concentration to the crystalline structure, morphology and size distribution of the TiO 2 particles were systematically investigated. There were observed that the TiO 2 has a uniform spherical shape with particle size around 200–500 nm. Increasing the precursor concentration resulted the size distribution shifted toward the bigger size. The crystalline structure of produced TiO 2 showed the mixed phase of anatase and rutile and has a large specific surface area~ 850,343 m²/g.