Proceeding of the Joint International Symposium on Deformatuon Monitoring. 2-4 November, 2011. Hong Kong. China. Report. We are currently carrying out a time series analysis of the Earth gravity field changes observed from twin GRACE (Gravity Recovery and Climate Experiment) satellites. Analysis of the monthly GRACE data set will explore co-seismic displacements for the Maule earthquake (Mw = 8.8) that occurred on February 27, 2010 in Offshore Bio-Bio, Chile. Since the beginning of 2002, the GRACE monthly solutions of the Earth's gravity field are available; hence this time-variable gravity field solution contains information on the co-seismic change of the height anomaly for this earthquake. Initial results seem to indicate the anomalies caused by the co-seismic deformation from the 2010 Mw = 8.8 Maule earthquake is -6.5 mm for the variations of the height anomaly. However, how to carefully eliminate the hydrological signals was the main hurdle to negotiate.