Background:  Adherence to periodical screening for sexually transmitted infection among female sex works is a major concern. Here, studies says that Tamilnadu’s state female sex workers have obtained high STIs awareness and treatment seeking behavior for the self–identified sexually transmitted Infection. Though there is a high level of STIs awareness, 30.9% of FSW had at least 1 symptom of STI. This indicates that there is a lack of treatment seeking behavior and safe sex practice. The purpose of this study was to identify the individual FSW who plays a central role in STI treatment seeking behavior. Objective: The objectives of the present study is  to map the existing networks of FSWs, identification of influential individual or key nodes within the network  who facilitate   Information flow on treatment seeking behavior  by using social networks analysis Method: Structured questioner was used for interview female sex worker using exponential snowball method to measure the social relationship for STI treatment seeking, motivated and accompanied for STI screening. And identified the central node for treatment seeking behavior using in – degree and page rank of sociometric measures of social network analysis. Findings:   A list of 152 FSWs social relationships mapped and analyzed the values of in–degree, page rank for above said activities. Out of this 152 FSWs, 26 FSWs had overall page rank value greater than two and 6 FSWs were having more than page rank three. This shows that information flows higher through this individual 26 FSWs compare to other. As this FSWs are indirect contact with 44 FSWs among the overall 152 FSW. Conclusion: The findings of this study establish that SNA could be tried out for mapping the network and central node by identifying the vital 26 FSWs for strengthening the periodical STI screening. This study, however, suggests that such analysis may help us to understand information flow for STI treatment seeking behavior and conceptualize self–reported infection. FSWs who weren’t directly into the implementation of STI screening program has contributed significantly. Thus, utilizing these 26 FSWs as a positive speaker would strengthen peridodical STI screening among FSWs.