An optical fiber cord includes: an optical fiber; and a cover material covering the optical fiber, the cover material being formed by braiding a plurality of yarns. Moreover, an abnormality detection system includes: the optical fiber covered with the cover material formed by braiding the plurality of yarns; a scattered light detector configured to detect scattered light occurring in the optical fiber and output data on intensity distribution in a longitudinal direction of the optical fiber; and a data processor configured to determine the presence or absence of an abnormality based on the data outputted from the scattered light detector.