The current study extends the exploration of online relationship building by examining how Business Next top 100 online sellers use the popular social network site Facebook to assist dialogic communication with their fans. A content analysis of Facebook fan pages maintained by Business Next top 100 online sellers (n=100) and individual posts which posted on those pages (n=2804) examined the use of dialogic features within the Facebook fan pages as well as the individual. The contraction process of social networking sites effectiveness indexes used literature review and content analysis. Those indexes were revised by reexamining the circumstances of Facebook. Four dimensions of indexes were ¡§Usefulness of information¡¨, ¡§Generation of return visits¡¨, ¡§Conservation of return visits¡¨, and ¡§Dialogic loop¡¨. 25 indexes were developed. Results indicated that online sellers which manage Facebook fan pages (76%) employed the dialogic strategies of dialogic loop mostly (M=16.76). It presents the highly interactive of Facebook fan pages. Interact games on Facebook fan pages which combine asking interesting questions and special discounts are significantly related with user responses.