The geothermal gradients in the fore-arc and back-arc of Ecuador were calculated through a lineal regression using BHT (bottom hole temperatures) measured at several depths and in different locations along the sedimentary basins. BHT was corrected by applying the AAPG empirical method and comparing it with BHT corrected by Horner method, DST and PVT data. In order to compare the fore-arc and back-arc geothermal gradients, AAPG-corrected BHTs were used. The fore-arc geothermal gradient is 14.2 °C/Km, whereas that for the back-arc is 23.6 °C/Km. The low temperatures registered in the fore-arc can be related with its oceanic affinity basement accreted to the continent, little or no presence of the asthenospheric wedge and/or entry of fluid-bearing sediments into the subduction channel. This special condition defines the "cold" feature of the equatorial fore-arc. Geothermal gradient maps for each region were generated using uncorrected BHT data. In the backarc region a confidence analysis was made, based in the amount of BHTs on different depths and the theoretical surface temperature. This analysis was not possible to do in the fore-arc, due to the scarce data available; nonetheless this map was created using a gradient calculated with at least three BHT at different depths. Both maps show indirectly local differences in the configuration of the basins, related with variations in its sedimentary infill and the disposition and type of basement. Special characteristic is the low gradient observed near the Andes, related with the Macuchi arc in the fore-arc and the Subandean in the back-arc.