The advanced boiling water reactor (ABWR) is designed to represent the next generation of boiling water reactors (BWRs), to be introduced into commercial operation in the 1990s. The response of the ABWR to loss-of-coolant accidents (LOCAs) was simulated in the full integral simulation test (FIST)-ABWR test facility. However, the emergency core cooling system structure was somewhat different from the current ABWR design. The LOCA experimental results of FIST-ABWR showed that a core was completely covered by a two-phase mixture and cooled by natural circulation without any rod heatup. The SAFER03 computer code has a newly developed evaluation model for the analysis of BWR LOCAs. SAFER03 analyses with the FIST-ABWR test data were performed to assess its ability to predict thermal-hydraulic responses for various postulated break locations in an ABWR. The analytical results indicate that SAFER03 accurately predicted pressure history, down-comer level response, and key phenomena, such as no core uncovery and no rod heatup. Consequently, it was confirmed that SAFER03 is applicable for ABWR LOCA analyses.