Pb(Mg1/3Nb2/3)O-3 thin films were prepared from modified alkoxide solution precursors and their dielectric and electromechanical characteristics were investigated. Preparation of the films is very sensitive to processing parameters. The influence of different seeding layers on the microstructures is discussed. Films show relaxer-like behavior, but with dielectric permittivity which is low (4500 at peak) compared to bulk ceramics and single crystals. Large electric de bias fields (up to 120 kV/cm) can be applied to the films. This de field reduces the permittivity, suppresses the frequency dispersion and flattens the permittivity-peak. No anomaly in temperature dependence of the permittivity associated with the held induced transition into, a ferroelectric phase was observed. The maximum field induced piezoelectric d(33) coefficient is around 85 pm/V and electrostrictive strains up to 1.6 10(-3) were measured with an electric field of 30 kV/cm.