Abstract: In order to real-time monitor changes of water salinity and dynamically analyze its perennial salinity distribution, this paper designed an in-situ high-frequency conductivity transducer with a buoy. The transducer uses a low power MCU (MSP430F149) and a SIM300 GPRS communication module, and the remote date acquisition is realized within the coverage of GPRS signals in water areas, such as rivers, lakes and aquafarms. The system was designed with a linear interpolation to compensate the temperature conductivity sensor, and the compensation accuracy is ± 5% FSC. The study can provide a feasible solution for online water monitoring in field waters.