This work presents results of geochemical exploration in the promising geothermal area of Mesillas, Nayarit, in the western border of the Mexican Volcanic Belt. The assessment of the geothermal resource was based on a geochemical approach which consisted in: (i) mapping and geological survey, (ii) chemical characterization of geothermal manifestations, (iii) diffuse flux analysis (CO2 and H2S), (iv) temperature at depth calculations using both classical and integrated multicomponent geothermometry.. Additional to the technical work, social dissemination of geochemical issues was attempted by designing and distributing a geomap among local people. The geological survey identified five andesitic units in an area of ∼1.5 km2, where 25 thermal springs discharge Na–CO3 water with temperatures between 47 and 90 °C, and pH ∼9. Geothermometric calculations indicate a bottom temperature between 125 °C and 130 °C. Andesites show high permeability generated by intense fracturing related with normal fault systems with trend NW-SE, SW-NE, NS, and EW. Surface hydrothermal alteration is mainly argillic with silicification. CO2 and H2S hydrothermal degassing are mainly restricted to thermal springs aligned in the NW-SE direction. Thermal springs with high temperature, highest degassing and high presence of hydrothermal alteration occur in the south-southwest zone of the geothermal area (MOL10, MOL13, MOL14 and MOL15); they correspond with NW-SE structural alignment. Furthermore, the estimated range of temperature at depth using geothermometers is 125–130 °C, and the surface temperature is on average 20 °C; considering local thermal gradient, it was estimated an equilibrium depth of 2.0–2.1 km. These results indicate that the Mesillas geothermal prospect may be classified as a medium temperature system with good permeability that may be exploited for electricity production as well as direct uses.