Nanocrystalline PbTiO3 particle/polymer hybrid was synthesized in situ through hydrolysis of modified metal-organics below 100℃. PbTiO3 precursor was synthesized from lead acetate, titanium isopropoxide and polymerizable diketonate ligand in 2-methoxyethanol. The modified PbTi alkoxide was hydrolyzed yielding PbTiO3 particles embedded in polymer matrix through chemical bonds. The nanocrystalline particles were identified to be PbTiO3 by EDX and electron diffraction. A fluid consisting of PbTiO3 particle/polymer hybrid and silicone oil revealed a typical electrorheological (ER) behavior on applying DC field. The ER behavior was found to depend upon the synthesis conditions of the hybrid.