The invention discloses a power grid stability margin visualized display method based a GIS. The method comprises the following steps of: obtaining measurement data of an electric power system wide area measurement system; carrying out state estimation on the measurement data of the electric power system wide area measurement system; directly reading data after state estimation correction; carrying out dynamic modeling according the data after the state estimation correction; and carrying out visualized display on a critical stable value and a stability margin of an equivalent electric power system. The power grid stability margin visualized display method has the advantages that equivalence processing on whole network data or on data outside the research range in the stability margin calculating process is omitted, the calculating time and resources are saved, and a huge economic benefit is generated. The regional stability margin is displayed in a geographical information map mode, the angle of stability condition display and judging is expanded from point and line to plane, so that people can globally grasp the stability condition of the electric power system more visually and effectively, better learning and application of control personnel are facilitated, and the stable operation of the electric power system is ensured.