Vehicles or ships each carry a magnetic force line sensor, a GPS position detector, and a data transmitter and travel within an observation area transmitting magnetic field data and position data to an earthquake prediction center. A telluric current induction field estimation unit of the earthquake prediction center estimates telluric current induction fields based on the received observation data. A telluric current estimation unit estimates telluric currents based on the results of estimating the telluric current induction fields. A telluric current induction field intensity change pattern generation unit generates patterns indicating the change over time of the intensity of telluric current induction fields. An earthquake prediction unit analyzes the state of distribution of the telluric currents and the patterns of change in the intensities of the telluric current induction fields and estimates a seismofocal zone, seismic intensity, and time of occurrence of a seismic event.