The　droplet　non-coalescence　characteristics　and　mechanism　under　a　DC　electric　field　are　investigated　by　comprehensively　using　high-speed　microscopic　experiments,　molecular　dynamics　simulations,　and　interface　dynamics　simulations.　The　researches　show　whether　two　droplets　coalesce　or　not　depends　on　the　evolution　of　liquid　bridge.　The　liquid　bridge　evolution　is　not　only　dominated　by　the　electric　force　F-E　and　the　capillary　force　F-i,　but　also　slowed　down　by　the　viscous　force.　The　relative　strength　of　F-E　and　capillary　force　F-i　relies　on　the　electric　capillary　number　Ca　and　the　maximum　liquid　bridge　radius　R*(max).　The　droplet　non-coalescence　is　more　likely　to　happen　as　the　Ca　increases　or　the　R*(max)　decreases.　Furthermore,　the　critical　value　Ca-c　for　droplet　non-coalescence　reduces　as　the　R*(max)　decreases.　The　ion　transportation　causes　uneven　distribution　of　ions　and　thus　strengthens　the　F-E,　resulting　in　the　non-coalescence.　These　results　provide　significant　guidance　for　efficient　demulsification　of　water-in-oil　emulsion.