A crankshaft flaw detection device (1) used for detecting flaws in the crank pin, web, and fillet section of a crankshaft comprises: a pair of shaft flaw detection heads (2, 3) configured so as to be capable of sandwiching the crank pin (C2) therebetween, and having a first probe (2b) capable of detecting flaws on the shaft surface of the crank pin (C2) or a second probe (3b) capable of detecting flaws in a fillet section at the base of the shaft; and a perpendicular surface flaw detection head (4) configured so as to be capable of coming in contact with the crank pin (C2) and having a third probe (4b) capable of detecting flaws in the side surface of the web (C3). The crankshaft flaw detection device (1) is characterized by the perpendicular surface flaw detection head (4) and the pair of shaft flaw detection heads (2, 3) being movable within the perpendicular surface