Abstract: This paper firstly summarized the main methods for identifying and extracting the abnormal disturbance of the ionosphere related to earthquake from the DEMETER satellite observation data. Then the modified pattern informatics (MPI) method, which is applied to extract the ionospheric disturbance anomaly from the French DEMETER satellite observation data, was mainly introduced. The results from the MPI method show that the abnormal disturbance of the ionosphere usually occurs about one month before an earthquake. Comparision of the MPI method with other methods shows that MPI method is more practical for earthquake prediction because the abnormal disturbance detected by other methods appears only a few hours to a few days before an earthquake and leaves only very short time for response. However, there is still a long way to go before MPI method can be applied to real time earthquake prediction. Finally, several issues about extracting ionospheric disturbance anomaly by MPI method are proposed to be solved in further study.