The invention provides an escalator safety device abnormality detection device and an abnormity detection method, which can be used to carry out safety switch check, position adjustment, and motion state of a checking mechanism without dismounting a driving chain from a driving wheel. The safety device abnormity detection device 16 used to detect the abnormal state of the safety device of the escalator 100 comprises inserting holes 34,36 used as connecting fulcrums of a connecting rod mechanism 30, an inserting part 19 used for temporary fixing the connecting rod mechanism 30, and a bolt head 18 disposed on one end of the inserting part 19, a connecting rod limiting part 17 disposed on the bolt head 18. The connecting rod limiting part 17 is in the shape of a fan column shape, and the central angle of the fan shape is smaller than 180degrees, and according to the inserting depth of the inserting part 19 with respect to the inserting holes 34,36, the corner part 17A is contacted with the driving chain 4.