Deep soil mass settlement monitoring system

The invention relates to a deep soil mass settlement monitoring system which is characterized in that a vertical drill hole is formed in a position where settlement monitoring is needed, a hanging hammer is placed at the bottom of the vertical drill hole, the hanging hammer is connected through a first end of a thin line sleeved with a casing pipe, and meanwhile the thin line is exposed out of thecasing pipe by a preset length. The casing pipe is fixedly arranged relative to the vertical drill hole, so that it is guaranteed that the hanging hammer can drive the thin line to descend together when the deep soil body sinks, and the casing pipe cannot move along with the thin line. And when the deep soil body is settled to a certain extent, the second end of the thin wire and the alarm switchplay a powerful role, and the alarm switch is converted into a closed state from an open state to realize power-on, so that an alarm signal is output. The scheme can be realized only by simple devices without professional equ