Ta2O5 is a wide-bandgap semiconductor that offers interesting applications in microwavecommunications, mainly related to the manufacture of filters and resonators whosesize is inversely proportional to the dielectric constant of the material. For that reason, inthis work we present a theoretical study, based on density functional theory (using PBEsoland hybrid HSE06 exchange-correlation functionals), of the electronic and dielectricproperties of the orthorhombic model -Ta2O5. We found that this model has a direct gap of2.09 and 3.7 eV with PBEsol and HSE06, respectively. Furthermore, the calculated staticdielectric constant, 51, is in good agreement with the reported values of other phases of thissemiconductor.