An insulating support is provided for vacuum switch tubes with actuator units to be used in switchgears, in particular in gas-filled units. The insulating support has a flatbed-type extruded plastic piece with a profile fitting around the periphery of the actuator unit of the vacuum switch tubes, with the ends of the insulating support being provided with attachment arms extending in opposite directions and containing screw beds arranged symmetrically in relation to the longitudinal axis. Such insulating supports are used for accommodating and securing vacuum switch tubes equipped with actuator units for switchgears.