Abstract: The slope instability of Washan Stope of Nanshan Iron Mine，Ma-steel，is increasingly prominent with the increase of mining depth.In view of this situation，the changing trend and scope of deep rock displacement and surrounding rock stress was found out through monitoring of surrounding rock stress and deep rock displacement.At the same time，the influencing level of blasting vibration on slope stability was obtained，and the stability of the slope was estimated.The variation of the stress and displacement in the process of mining was achieved based on FLAC3D numerical analysis software in mining simulation.Through contrasting with the evaluation results of the stability before slope monitoring，its reliability on slope stability was further verified.The conclusion is that if Washan stope is planned to continue exploiting downwards，it is necessary to strengthen monitoring or reinforce slope before excavating.

Key words: Open-pit mine, Stress monitoring, Displacement monitoring, FLAC3D