Abstract: To optimize the layout of soil moisture sensors in water-saving irrigation system, we proposed an interactive policy which was combined with global optimization genetic algorithms and improved weighted round layout theory. This approach was designed based on constraints of sensors performance such as the accuracy of coverage and overlay restrictions. With the help of bringing expert knowledge into the interaction and adopting decimal codes within the genetic algorithm, this interactive policy was easy to be updated and transplanted in other areas by cooperating with other algorithms or by adding extra parameters. The experimental results indicated the optimal approach proposed in this paper decreased the cost by 17.5% than quadrangle layout approach and by 34.0% than hexagon layout approach.