A component monitoring system monitors whether a component fitted to a working machine is a genuine component, and prevents the use of a counterfeit product or the like. A working machine is provided with a plurality of exchangeable components, and each component is provided with a wireless tag. A component ID is stored in advance in the wireless tag. When, on the side of the working machine, a component exchange timing or an engine starting timing is detected, the component ID stored in the wireless tag is acquired, and is transmitted to a working machine management device. The working machine management device checks the component ID which has been received from the working machine and a component ID which is stored in a component ID storage means against one another. And, if these two component IDs do not match one another, an abnormal state detection means outputs a warning signal.