Abstract: Aiming at the problem that it is difficult to monitor and analyze the operation status of the naked seedling transplanter in China at present, a monitoring system for naked seedling transplanter of sweet potato is designed, which integrates multiple sensors. The system mainly includes two parts: information collection and processing, remote monitoring. The diffuse reflection laser sensor and rotary encoder are used as the information collection mechanism, the PLC is used as the information processing and logic controller, and the operating conditions of the transplanting machine are sent to the OneNet remote cloud platform in real time in combination with the DTU device. The mobile phone APP software is developed based on the MIT APP Inventor, and the mobile phone access to the OneNet cloud platform is used to realize the remote viewing and analysis of the transplanting information. The accuracy of the monitoring system for missed planting of the key device was tested. The test results showed that the maximum monitoring accuracy of the monitoring system for missed planting was 98.45% and the average monitoring accuracy was 98.15% under three transplanting frequencies, which could better meet the requirements for accurate monitoring of naked seedling transplanting of sweet potato.