In this paper,the layout monitoring situation and monitoring effect of cross-fault mobile deformation monitoring site in North China are analyzed. Then,on the basis of the consideration of cross-fault mobile deformation measurement criterion,monitoring requirement of controllability,uniformity,purpose and monitoring sites' monitoring effect,etc.,and with the research result of local fault activity and seismic activity,the cross-fault mobile deformation monitoring site's layout optimization result is given in North China. This layout optimization result eliminates the monitoring seismic activity blind area of cross-fault flow deformation network and helps to improve the monitoring seismic ability of cross-fault flow deformation area network in North China.