Abstract: An electrostatic filter utilizes a series of parallel plates which are charged at differing potentials and separated by porous filter material to remove particulate matter from dielectric fluids. The filter includes a fluid tight housing which is constructed to include an easily removable filter cartridge comprised of a shell that conforms to the housing and includes the plate and porous filter elements. The housing further includes a quick disconnect end cap that includes an electrical connection to a power supply. An electrically conductive spring is interposed between the power supply and an adjacent plate. This arrangement allows for a very simple, safe, quick and cost effective procedure to change filter cartridges. The cartridge structure additionally allows for the easy checking of proper continuity between electrodes during the cartridge assembly.