The invention discloses a metal circular workpiece detection device. The metal circular workpiece detection device comprises a detection device and a grasping device arranged next to the detection device. The detection device comprises a workpiece fixing seat, a roundness detection mechanism, a CCD detector and a flaw detection device, wherein the roundness detection mechanism and the CCD detectorare separately arranged above and below the workpiece fixing seat, and the flaw detection device is arranged on one side of the workpiece fixing seat. The grasping device comprises a driving device arranged on one side of the workpiece fixing seat, a feeding grasping mechanism and a discharging grasping mechanism, the feeding grasping mechanism and the discharging grasping mechanism are arrangedseparately and movably on the driving device, and the feeding grasping mechanism and the discharging grasping mechanism are arranged corresponding to the workpiece fixing seat. The invention further discloses a using method of the metal circular workpiece detection device. According to the metal circular workpiece detection device and the using method thereof, the design is reasonable and ingenious, the process of feeding, detection and discharging can be realized automatically, the real-time detection and monitoring of a workpiece is carried out, the detection effect is good, the detection speed and efficiency are high, the data is accurate and objective, the metal circular workpiece detection device is suitable for detecting the workpieces of various sizes, and a wide range of applications is achieved.