Emergency planning is the guidance in emergency responses and its performance can influence the whole rescue process. Hence aiming at improving the emergency planning performance and promoting the rescue efficiency, there is an urgent requirement to appraise the performance of emergency planning. A mature emergency system is the premise to ensure emergency planning to be performed perfectly. Firstly, the maturity of emergency system is evaluated qualitatively by comparing the challenge caused by potential risk and emergency capability formed by emergency system. If the emergency capability can encounter the potential risk, the emergency system is viewed as mature. Secondly, functional attributes are analyzed and the performance assessment index system of planning is set up by characterizing the attributes in detail. Thirdly, according to the hierarchical characteristics of the index system, the performance assessment method for emergency planning is put forward through the combination of Analytic Hierarchy Process (AHP) and fuzzy theories. In the method, defuzzification is introduced so as to achieve the integrated performance of emergency planning and performance taxis of all assessment indices. The taxis from priority to inferiority of performance indices can be used as references to improve the emergency planning. Finally, the application of the method in a petrochemical materials storage depot indicates that the disadvantages existing in the system and emergency planning can be found out through the assessment results and the advices given to the depot improve the emergency system maturity and the emergency planning performance. (C) 2008 Elsevier Ltd. All rights reserved.