A rolling bearing comprising: an outer ring , the outer ring having an outer peripheral surface and an inner peripheral surface; an inner ring disposed coaxially with the outer ring, the inner ring being on the inner peripheral side of the outer ring; multiple rolling elements disposed between the outer ring and the inner ring; a housing presenting an inner peripheral surface holding a portion of the outer peripheral surface of the outer ring that is located directly above a given rolling element by contact with the inner peripheral surface of the housing over the whole circumference of the outer ring, the housing further being provided with an undercut; and a strain gauge configured to detect strain of the outer ring or the inner ring, wherein: the strain gauge includes at least one resistor formed of a Cr composite film and is positioned at the undercut of the housing such that the strain gauge does not contact the housing; the at least one resistor includes two resistors arranged in a same direction as an arrangement direction of the rolling elements so as to correspond to a spacing between rolling elements that are next to each other; and the two resistors are disposed on a side of the outer peripheral surface of the outer ring opposite a side of the outer peripheral surface intended to bear a preload (F). an outer ring , the outer ring having an outer peripheral surface and an inner peripheral surface; an inner ring disposed coaxially with the outer ring, the inner ring being on the inner peripheral side of the outer ring; multiple rolling elements disposed between the outer ring and the inner ring; a housing presenting an inner peripheral surface holding a portion of the outer peripheral surface of the outer ring that is located directly above a given rolling element by contact with the inner peripheral surface of the housing over the whole circumference of the outer ring, the housing further being provided with an undercut; and a strain gauge configured to detect strain of the outer ring or the inner ring, wherein: the strain gauge includes at least one resistor formed of a Cr composite film and is positioned at the undercut of the housing such that the strain gauge does not contact the housing; the at least one resistor includes two resistors arranged in a same direction as an arrangement direction of the rolling elements so as to correspond to a spacing between rolling elements that are next to each other; and the two resistors are disposed on a side of the outer peripheral surface of the outer ring opposite a side of the outer peripheral surface intended to bear a preload (F). the strain gauge includes at least one resistor formed of a Cr composite film and is positioned at the undercut of the housing such that the strain gauge does not contact the housing; the at least one resistor includes two resistors arranged in a same direction as an arrangement direction of the rolling elements so as to correspond to a spacing between rolling elements that are next to each other; and the two resistors are disposed on a side of the outer peripheral surface of the outer ring opposite a side of the outer peripheral surface intended to bear a preload (F). <EOS>