In order to realize online realtime monitoring of fullface TBM and shield scraper wear, a new realtime monitoring system of scraper wear was developed. The system is composed of four parts: wear sensing module, data reading and sending module, wireless receiving gateway and machine software. The wear sensing module is the core of the system. The wear sensing module at the surface of the scraper can sense wear in real time, the data reading and sending module transfer signal to the wireless receiving gateway, and then send the data to the host computer software. In addition, the indoor calibration test was carried out, and the formula for monitoring the wear of scraper was proposed according to the test results. The tool wear test platform was used to verify the feasibility test. The experimental results show that the scraper wear sensing module is stable and not distorted in muddy environment under the protection of epoxy glue. The wear amount error is controlled within 1 mm, and the indoor wireless transmission distance is up to 30 m. The monitoring system can realize the realtime monitoring of blade wear with high accuracy, and can effectively solve the TBM and shield scraper wear realtime monitoring of engineering problems.