Abstract: Taking some impervious wall as an example, combined with monitoring data and the arrangement of monitoring instruments, the characteristics of its stress deformation was analysed and mechanism was discussed. The deformation(deflection) of impervious wall mainly relates to horizontal pressure, and grouting pressure makes the monitoring data in vertical approach of the river not so regular. The strain of impervious wall mainly relates to vertical loads, the friction which caused by uneven settlement between the wall and overburden layer exerts influence on the spatial distribution of the strain.