A connecting rod inspecting device is provided with a work table for placing a connecting rod in a status where the connecting rod is positioned at a prescribed position; a slide unit for reciprocating the work table along the horizontal direction; and first to fourth distance sensors for measuring a step quantity (D) of a step part by irradiating measuring planes composed of curved surfaces with laser beams and measuring distances between the sensors and the planes irradiated with the beams. Conforming/nonconforming judgment is made by the measured step quantity (D) and a range of allowable quantities previously set.