Abstract: A microbe drain barrier for insertion in the drain of a sink or the like to prevent microorganisms from reentering the sink from the drain. The barrier includes a length of thin-walled heat-resistant, electrically non-conductive tubing having a heat conductivity in the axial direction of not more than about 3 Btu/hr/ft.sup.2 /.degree. F./ft. The barrier includes electric heating means for heating the tubing to an inner surface temperature sufficient to prevent the growth of microbes thereon. Connector pipes extend axially outwardly from the tubing for mounting the tubing in a drain pipe such that drainage through the drain pipe is required to pass through the tubing. The connector pipes are secured to the tubing by annular insulating rings which isolate the tubing and electric heating means from the connector pipes.