Due to the persistence of fertility below replacement level and the need to identify relevant factors, In this article, we examine the impact of feeling of security on the number of children ever born, ideal, intention, and the intention to have another child. Using the Married Lifestyle Survey data, 1189 married men and women in Tehran, where the woman was less than 50 years old and fertile, selected in a multi-stage cluster method and used in the final analysis. The results showed that the mean of ideal children number in the respondents was more than two children (2.13), the intended children number was 1.91, the children ever born number was less than the replacement level (1.41) and 36/9 percent of the respondents intended to have another child. There was a significant relationship between the feeling of security and the number of children ever born, ideal and intended. Also, logistic regression models showed a significant effect of feeling of security in exit of childlessness, one-child and two-children. Policy suggestions in order to increase childbearing, based on a suitable context to reduce risky situations and increase the feeling of security in various economic, public, judicial and political dimensions, including job security and adequate income, political stability and immunity from any offense.