Background: happiness is a drive and constructive force of life. A person feels wellbeing under different effective factors. Religious dogmatism that has an influence on the entire world is one of the depreciatory factors of happiness or wellbeing. The current study decided to analyze the relation between dogmatism and wellbeing, and according to a model, answer the following question: how does religious dogmatism decrease wellbeing.Methods: This study is a correlation research. Population of study includes all people with 30-50 yr old who live in Tehran, Iran, in 2015. Among all, 180 subjects were selected as in access sample. The Oxford happiness questionnaire and Rokeach dogmatism scale were used. Data were analyzed by Pearson correlation test.Results: There is a significant negative correlation between dogmatism and happiness (α=0.05).Conclusion: Dogmatism is one of the factors that have a negative effect on wellbeing. Religious dogmatism is the most dangerous factor against wellbeing. Dogmatic individuals have an inflexible cognitive system that emerges as a stable personality trait and decreases their adjustment with environment. Affective well-being and cognitive wellbeing are affected by individual adjustment. Therefore, in dogmatic individuals with low adjustment, the decrease of affective well-being and cognitive wellbeing is inevitable. This process will result in decrease of happiness and increase of aggression.