The 13th Workshop on SAR Image Signal Processing was held at Josaphat Laboratory (JMRSL) by Prof Josaphat on 25 April 2015 for new students and other laboratory students of Center for Environmental Remote Sensing, Chiba University and companies staffs. This workshop held to enrich the knowledge of students relating synthetic aperture radar (SAR) system and signal processing, including designing SAR system for unmanned aerial vehicle (UAV), aircraft and spacecraft.