Abstract: A method is presented to resolve the problem of collecting of soil compaction information in real time for use in farm prescription management in precision agriculture. A continuously measuring soil resistance system was designed and developed. The system included an octagonal sensor, a mechanical part, a soil resistance information collection system, and a steel framework for mounting on a tractor with 3-point hitch. The tractor velocity was 1 m/s when the system was used in field. The soil resistance information sampling rate was 300 Hz, and data were saved to a file correspond to GPS position. The measuring precision of system in lab was 93.4%. The data of the test in farm fields showed that the system was stable, fast and able to measure soil resistance, and defined TRI (soil tillage resistance index) could be used to express the state of soil compaction.