To scientifically preserve the earthen city wall site of JianKang from the Six Dynasties in Nanjing, the structural performance of the earthen wall sites strengthened with anchor rods was analyzed with ANSYS. The relationship between the structural safety of the earthen wall site and important parameters including the length, angle diameter and spacing of anchors, thegrade of the side slopeand water content were then investigated.The structural safety factors and the optimal technical parameters for the anchor reinforcement of the earthen wall site were determined. In order to verify the accuracy of theoretical analysis and construction feasibility, pullout tests of anchor rods and tests of grouting materials.Finally, based on theoretical analysis and test studies, an adaptive design for strengtheningthe earthen wall site with stainless anchor rods and modified mud grouting was proposed.