According to the requirements of the synchronous sampling system of seabed sediments insitu measurement, the temperature probe rod was designed, and the temperature measuring unit of the system was constructed and tested. The temperature measuring unit was used to collect the temperature sensor data collected by the STM32F407 main control board. Taking the DHX010 thermostat as the standard, the static and dynamic measurements for the NTC10K sensor, temperature probe and Pt100 sensor were carried out. The maximum steadystate error of NTC10K is 0.71 ℃, the maximum steadystate error of temperature probe is 0.62 ℃, and the maximum steadystate error of Pt100 sensor is 0.8 ℃. The dynamic response time of the NTC10K sensor, the temperature probe and the Pt100 sensor when the temperature step changed from room temperature to 15 ℃ was measured. It provides reference for the temperature measurement and motion control for the seabed in situ observation system.