Abstract: Objective Focusing on the limitations of conventional methods,a new method for testing the stabilityof landslide monitoring network for long and narrow areas was studied.The process was divided intothree steps:Firstly,the relatively stability points were identified in the ITRF frame;Secondly,thereference points displacement was calculated in the local reference frame as defined by relatively stabilepoints;Thirdly,a displacement significance test was used to analyze the stability of these referencepoints.Using GPS observations(2008-2011)of a landslide monitoring network in the Three Gorgesreservoir area,the stability of all reference points was tested:finding moved reference points duringthree years of high water impoundment,with a horizontal displacement of the moved reference pointsof more than 4cm,with a maximum of 79.4cm.The displacement direction of unstable referencepoints was physically inspected along with the geographical environment,revealing that they wereconsistent with the results obtained from the proposed testing method.