In this study, we examine the spatio-social challenges of Tehran, from the urban planning point view, with the approach of the factors associated with sexual risk behaviors of street women (behaviors that were associated with sexual activity) Through field survey and preparation of the questionnaire. A cross-sectional study in order to measure the factors that lead to increased risky sexual behaviors and measure the quality of life on the Sex workers, are designed. Participants in the study are Sex workers who registered in the centers for vulnerable women. A total of 250 of these women selected based on clustering procedure. Questionnaire with 36 questions were written. According to the results, more than half of the women, aged between 17 and 35 years and the age group 26-30 years was the most common. In terms of marital status, the highest rates were related to divorced women and widows respectively. A very low number of people had a private home and more than half of them live in warm and rental houses. The relationship between drug use and age was significant and 81 percent of these individuals experienced drug use and this figure for alcohol was 61%. In overall, results showed that comprehensive spatio-social organization plan, regardless of considering vulnerable people would be incomplete