A GIS pipe deformation monitor alarm device comprises a sliding support, an indication part and an alarm part. That sliding support is provide with a sliding block slidable along the sliding support,the sliding block is in contact with a pipe, the displacement amount of the pipe and the sliding block can be displayed in the indication part, and the indication part is electrically connected with the alarm part. The device has the advantages of simple structure, small volume and capability of saving space. When the deformation of the pipeline reaches the warning point, the device warns, and thedisplacement of the GIS pipeline sliding bearing can be directly observed, so as to judge the deformation of the pipeline.