The invention discloses a deformation monitoring method, comprising the following steps of: 1. installation of a monitoring device and establishment of a space coordinate system; 2. detection of an inclination angle of an object to be tested; 3. compensation of an inclination state of the object to be tested; 4. monitoring of a settlement state of the object to be tested; and 5. monitoring of a cracking state of the object to be tested. The deformation monitoring method disclosed by the invention has the advantages of reasonable design, low cost, time saving, labor saving, small cost, and capability of obtaining deformation states such as inclination, settlement, cracking and the like of buildings, structures and slopes, and performing real-time monitoring, so that forecast can be proposedin time, prevention measures can be conveniently taken, and the practicability is high.