Background: Sex work is a growing phenomenon triggered by a number of causes. The current study uses a qualitative method to investigate the reasons why women participate in sex work in Tehran. Methods: The statistical population consisted of all female sex workers in Tehran, Iran, from which 22 individuals were chosen via snowball sampling. In-depth interviews were conducted for data gathering, and traditional content analysis was used for data analysis. Graneheim and Lundman's method was utilized to evaluate the data, and Guba and Lincoln's criteria were employed to determine the research's strength and transferability. Results: The results of the data analysis were divided into five categories (or themes) and 19 subcategories. The categories were familial instability, societal pressure, consumerism, social insecurity, and a meek and inefficient personality. Conclusion: Sex work may be avoided by raising women's social status, providing greater economic assistance, making society safer, particularly in workplaces, improving intra-family connections, boosting self-esteem and self-efficacy, and teaching them how to deal with life's issues.