Abstract: According to relevant national information security standards and basic evaluation requirements,combined with the characteristics of ATC automation system,the main factors affecting the ATC automation system information security are analyzed and the information security evaluation system is proposed．Then based on expert evaluation me-thods and evidence fusion theory quantifiable assessment method is proposed which is easy to be implemented,and the subjectivity of expert opinions will be removed because of evidence fusion algorithm．Finally,according to an example the proposed evaluation method and fuzzy evaluation method were compared.

Key words: Air traffic control automation system,Information security evaluation,D-S evidence fusion theory