Considering Navier-Stokes equation, penetration of a tip in viscous film was considered allowing acquisition of viscosity from experimental data. Viscosity of thin (< 500 nm) films as a function of temperature in the range of 25-200 degrees C was measured with the rheological indenter for thermoplastic polymers and (as a function of annealing temperature and annealing time) for thermocurable polymers with submicron spatial resolution. The approach could be used in design, tailoring, and optimization of soft materials for different applications. (C) 2007 American Vacuum Society.