Parisa Zeraatiyan - Master of Industrial Management, Department of Management, Payam -e -Noor University, I.R. of IRAN
Meysam Alamdari - Master of Public Administration, Department of Management, Payam e Noor University, I.R. of IRAN, An employee in Ministry of Justice
Roqiyeh Keshvarian - Master of Public Administration, Department of Management, Payam e Noor University, I.R. of IRAN, An employee in Ministry of Justice
Marziyeh Hajipour - Master of Public Administration, Department of Management, Payam e Noor University

Proposing a method for identifying and prioritization of vital factors of knowledge management by means of Fuzzy DEMATEL is the final objective of the present research. This study is of the applied researches and descriptive- survey in which the questionnaire has been utilized for collection of the relevant data. We use fuzzy decision matrix to determine the importance of these factors from viewpoint of experts in the statistical sample rather than analysis on vital factors of knowledge management. After implementation of the suggested method, the resultant findings from ranking of these factors were shown by means of DEMATEL (Decision Making Trial and Evaluation Laboratory) technique in which the financial and non- financial motivational reward factors possess the highest significance and preference as the factors of cause group namely motivating role and they affect on total system at the maximum level while the factors of knowledge collection and knowledge creation were characterized as thefactors of effect group with the least preference and this means that these factors are extremely affected by other factors and they are optimized by optimization of other factors.

Knowledge Management (KM), Vital Factors, Fuzzy DEMATEL Technique, Fuzzy Set Theory