In this paper we present the results of the analysis of symmetric nanowaveguides of two types: dielectric/metal/dielectric and metal/dielectric/metal. In the analysis, the following metals were used: gold, silver and aluminum. Calculations have shown that from the point of view of minimizing the thickness of the waveguide and the minimum absorption during the propagation of the optical wave in the waveguide silver is the most appropriate to use in the waveguide structure of the metal/dielectric/metal.