Manual inspection and testing of threaded components, specially in high volume manufacturing processes are time consuming and costly. There are three different types of error which may occur within the tolerance zone specified by the metric thread ISO system, which are as follows: (i) Error of the flank angle. (ii) Error of pitch over the length of fitting. (iii) Error of effective diameter. Additionally, material build-up which blocks the threaded zone may also render the component to be rejected. These error may occur due to the manufacturing process itself, either by cutting or rolling, such as tool and die wear, materials defects , etc. This thesis describe the design and development of an automatic inspection system for threaded components. The system consists of a mechanical sensor, which is interfaced to a PC and the operational tracing cycle of the system is controlled to carry out the following operations. (1)- Belix path inspection. (2)- thread form inspection. The results of the helix path and the thread form tracing are presented for the ISO metric thread: (M6), <M8), and (M16), together with the operational cycle.