The invention provides a power resistor comprising a first reverse terminal piece and a second reverse terminal piece, a resistance element, at least one subsection conductive strip, and at least one opening area, wherein the resistance element is formed by a plurality of resistance element sections, and is located between the first reverse terminal piece and the second reverse terminal piece; the subsection conductive strip is used for separating the two resistance element sections; and the opening area is located between the first reverse terminal piece and the second reverse terminal piece, and is used for separating at least two resistance element sections. The division of the resistance element sections is beneficial to diffusing heat inside the power resistor. The power resistor or other electronic components can be packaged by a following manner: the power resistor or the other electronic components are jointed to heat radiation fins by using a heat conduction and electric insulating type material.