Life insurance, as one type of insurances which supports insured’ s family against premature and pre-retirement death of head of the family, has been attracted much attention in recent years. However, evidences indicate public unwillingness to buy life insurance. The current study aims to investigate and prioritize the affecting factors on unwillingness to buy life insurance in Guilan province. For this purpose, first, the affecting factors were identified by reviewing the theoretical literature. Next, these factors were sent to 384 customers in form of a questionnaire which the statistical analysis of their responses leads to determination of 18 more important factors. Hence, many of these factors have interactions with the others. Hence, fuzzy DEMATEL technique is used to determine critical factors. Next, the identified factors were sent to the managers of 45 Iran insurance agents in Guilan province in form of a fuzzy DEMATEL questionnaire. The results of data analysis using MATLAB 2014 software showed that the critical factors influencing unwillingness to buy life insurance in Rasht city are: (1) from influencing point of view: income level, educational level, inflation rate and recession, (2) from to be influenced point of view: life expectancy, saving tendency, expectations levels and life standards and (3) from sum of influencing and to be influenced point of view: life expectancy, income level, life standards and educational level. Finally, suggestions are proposed to the insurers in order to increase the willingness in life insurance.