The　evaporation　characteristics　of　a　sessile　droplet　under　a　direct　current　electric　field　were　numerically　investigated,　and　a　numerical　model　was　developed　based　on　the　arbitrary　Lagrange-Euler　method,　combining　the　flow,　heat　transfer,　vapour　transport,　and　electrostatic　equations.　The　simulations　were　validated　to　be　in　good　agreement　with　previously　reported　experiments.　The　results　demonstrate　that　the　electric　field　can　enhance　the　evaporation　of　the　sessile　droplet　with　different　evaporative　cooling　numbers　(initial　electric　field　intensity　E0　=　280　kV　&　sdot;m　　1;　32.9%　decrease　in　the　evaporation　time　for　water)　by　the　following　three　methods:　increasing　the　surface　area　of　the　droplet　evaporation　(2.6%)　through　the　electric-field-induced　deformation,　improving　the　heat　transfer　efficiency　between　the　droplet　and　substrate　(droplet　average　temperature　increases　by　2.3　K)　through　the　internal　vortex,　and　by　enhancing　the　shearing　effect　on　the　vapour　layer　(450.3%　increase　in　vapour　diffusion　distance　dc)　through　the　external　vortex.　Additionally,　the　evaporation　of　a　sessile　water　droplet　undergoing　thermocapillary　convection　is　further　enhanced　under　the　electric　field　(E0　=　280　kV　&　sdot;m　　1;　20.0%　decrease　in　the　evaporation　time).　As　the　inhomogeneous　temperature　distribution　inside　the　droplet　was　eliminated　by　thermocapillary　convection,　the　evaporation　efficiency　was　dominated　by　the　increased　surface　area　of　the　droplet　evaporation　and　the　enhanced　shearing　effect　on　the　vapour　layer.　These　results　will　provide　a　better　understanding　of　the　electro-hydrodynamic　enhanced　droplet　evaporation.