PALSAR-2 (Phased Array type L-band Synthetic Aperture Radar-2) is a spaceborne L-band SAR (Synthetic Aperture Radar) system installed on Japanese Advanced Land Observing Satellite-2 (ALOS-2). PALSAR-2 is expected to provide valuable data for global monitoring and disaster monitoring. To meet the variety of demands, PALSAR-2 provides various operational modes. This paper describes the overview of the calibration plan of PALSAR-2. Since PALSAR-2 have more than 1,000 operational modes, effective and efficient procedure is crucial. The process is divided in three different phases; pre-launch calibration, check-out phase (C/O phase) after the launch, and image calibration phase. The overview of each phase is described.