Introduction: The relational characteristics of an answerer on a social networking site can be used as cues to assess the credibility of an answer. This study examined the effects of different numbers of followers and friends of an answerer on readers' perceived credibility of an answer posted by the answerer in the context of Facebook. Method: We conducted two experiments to examine the effects of different numbers of followers and friends on the credibility perceptions of an answer on Facebook, respectively. Their influences on three dimensions of credibility were examined, namely: believability, trustworthiness, and accuracy. Analysis: The data were analysed using t-tests and two-way ANOVAs (analysis of variance). Results: We found that participants perceived an answer posted by an answerer with more followers or friends as more believable and trustworthy, but not necessarily more accurate. Conclusion: Despite the popularity of social networking sites as a place for information seeking, the effects of relational characteristics of an information provider have been little examined. Results of this study show that system-generated relational cues (i.e., number of friends and followers) likely exert a larger influence on certain dimensions of perceived credibility of an answer (i.e., believability and trustworthiness).