The necessity of minimization the electrical and electronic devices such as thermistors and resistors, led to developing a new obtaining technique: thick film deposition of materials for thermistors or resistors on a suitable support. To be deposed, the materials with desired properties (insulator or semi-conductor), in a nanometric powder form must be mixed with a film generating polymer solution or dispersion, to obtain a paste with a suitable viscosity. This paste will be deposed by lithographic technique on the desired support. Until now, the reported recipes contain polymer solutions in organic solvent. The thinner and the washing solutions used are also organic. It is well known that the organic solvents are not only expensive but also toxic and dangerous for environment. This paper presents a new method for obtaining thermistors and resistors pastes by dispersing the metallic oxides powder in an ecological aqueous polymer solution.