In wireless sensor networks, anchor positions play an important role for high localization accuracy. Planning an efficient path for mobile anchor nodes (MN) is critical for required anchor positions. In this work, an adaptive path planning algorithm is proposed for mobile anchors based on Gauss-Markov mobility model. The approach, which the velocity adjustment, the perpendicular bisector and the virtual repulsive strategies are combined based on Gauss-Markov mobility, is improved by developing a grid based virtual repulsive force strategy. To enhance the localization accuracy, the surveillance area is divided into grids and the grid based virtual repulsive force is applied to the MN if it is located in an anchor dense area. The simulation results show that defining a grid based virtual repulsive strategy increase the localization accuracy and cover more surveillance region using less energy.