Abstract: In view of the problems that the operation depth depends on manual monitoring during the trenching operation, the accuracy is low, and the manual workload is large, a trenching depth monitoring system based on LabVIEW is developed. Real-time monitoring, calculation, display and storage of trench depth and other parameters; in order to reduce the impact of operating environment and machine jitter on data, this paper uses three filtering methods: median filtering, Kalman filtering, and wavelet noise reduction-Kalman filtering. The data is filtered and corrected. Test verification shows that the system can monitor the parameters of trench depth, average value of trench depth, standard deviation of trench depth, stability of trench depth, operating time and other parameters in real time during trenching operation, compare the three filtering algorithms, wavelet noise reduction-The Kalman filter has the best noise reduction effect, and can realize the filter correction processing of the data. The corrected system has better accuracy and can meet the system design requirements.