Abstract: An oil-removal structure for range hoods which is characterized by a water container integrally formed with an air-guiding case, into which at least one electrothermal element may be positioned to heat water contained therein so that an oil meltable temperature may be reached. At this point, oily residual on the air-guiding case and exhaust fans of range hoods may be melted and can flow into an oil collector, and the range hoods can be cleaned without the effort required to dismount and disassemble them.