The entry condition of the Severe Accident Management Guideline (SAMG) for APR1400 has been evaluated on the basis of the Core Exit Temperature (CET) and Peak Cladding Temperature (PCT) calculated by the MARS-KS code. Although the APR1400' is a new type of reactor in Korea, if has been used the same entry condition to the SAMG as the former version of reactor. This study models the APR1400 with a system analysis code, i.e., the MARS-KS code. Then three initiating events which contribute 80 percent to the Core Damage Frequency (CDF) are selected as reference accidents to figure out the validity of the entry condition: Station Black-Out (SBO), Small- and Medium-Break Loss-Of-Coolant-Accidents (SBLOCA and MBLOCA). In order to verify the SAMG entry condition, the times to three important points, i.e., the current SAMG entry point (CET 923K), effective transition point, and fuel damage point (PCT 1255K) have been compared for each scenario. The conclusion reveals that the current SAMG entry condition properly indicates the fuel damage point and effective transition point for the events. (C) 2014 Elsevier Ltd. All rights reserved.