The invention discloses a seabed landslide monitoring device and method based on an MEMS sensor, and belongs to the technical field of seabed monitoring. A monitoring unit consists of a plurality of monitoring subunits which are connected in series. The monitoring unit is placed in a protection cover. The monitoring unit enables a monitored signal to be transmitted to a processing unit. The processing unit enables the processed signal to be transmitted to a computer terminal. A power module supplies a working voltage to a data processor. The MEMS sensor is fixed in a long pipe through a damping piece. One end of the long pipe is connected with one end of a soft connection pipe. The power module is connected with the MEMS sensor, and supplies the working voltage to the MEMS sensor. The MEMS sensor is connected with a data input port of the data processor. The data processor enables the processed data to be transmitted to the computer terminal. The device and method can achieve the monitoring and data recording of the changes of multiple layers of a seabed, achieves the monitoring of a single point to a plurality of points so as to form a three-dimensional monitoring plane, provides visual data for the research of the changes of the stratum of the seabed, and provide information support for the early-warning services of the seabed landslide.