The optimal sampling strategy is the balance between sampling intensity, cost analysis and research accuracy, namely, getting optimal precision through minimum cost. Sampling designs at home and abroad mostly use the model to optimize the sampling strategy. Based on the results of the traditional preliminary sampling method, it is not suitable for the preliminary sampling design. The existing representative grade method ignores the influence of the different coordination factors, which cannot use information of qualitative factors, and the results were affected by subjective parameters such as membership thresholds. In order to overcome these shortcomings, a method of soil sampling design based on priority was proposed, which was able to empower each synergistic factor, transfer information completely and accommodate a wide range of qualitative and quantitative synergistic factors in aided design. The results showed that the information carried by the priority sampling point set was closer to the total sample point set than the hierarchical sampling point set and the random sampling point set. The weight of the coordination factor was an important parameter of the soil sampling design based on sample priority, which had a certain influence on the result in terms of spatial distribution trend and interpolation error. The sampling design method can meet the needs of region sampling, improve the sampling efficiency and quality, and provide references for the designs of the other soil sampling schemes. Additionally，sampling benefit (ratio of variation in sampling accuracy to variation in sampling cost) can provide guidance for further determination of reasonable sampling numbers to some extent.