The electrical deposition in an over-plating technology was explored under different line spaces and line widths and the effect of geometries,such as a line space/line width ratio,and the deposition velocity during the over-plating was investigated by using numerical simulations. Then,the deformed meshes were also applied to suit to the boundary grows of plated microstructure with the deposition. The numerical results indicate that the difference of deposition velocity between the two adjoined plating lines is small and the depositing velocitie of the lateral and vertical directions are almost the same when the ratio of line space to line width is larger than 12. But the depositing in lateral direction will be constrained when the ratio of line space to line width is smaller than 6. The deposition can stop in a hole between the two plated lines and can cause the plating defect,for the smaller the line space/line width is,the bigger the ratio of leteral deposition velocity to vertical deposition velocity is. Experiments also show that the plating defect mentioned above can be removed by a technical method using a second seed layer on photoresist.