An insulated earthing switch for encapsulated, gas-insulated high-voltage switchgear assemblies is characterized in that an encapsulation-side earthing switch contact, a measuring electrode and an earthing switch housing are arranged altogether on a single earthing switch mounting side, and an encapsulation-side earthing switch contact and the measuring electrode are electrically insulated with respect to the earthing switch housing and the GIS housing. Exemplary embodiments contains an encapsulation-side earthing switch contact and a measuring electrode being electrically insulated from drive cables and drive rods; an encapsulation-side earthing switch contact in the form of a movable earthing switch contact or an earthing switch fixed contact; and an earthing switch housing being permanently electrically conductively connected to the GIS housing via a combined supporting and measuring flange.