In recent years, with appearance of social media era, the social media, such as Facebook, Twitter etc., have been used in various ways in healthcare areas. Some use them as a treatment tool for disease, others use them as a health information source. The more people get information and psychological supports from social media, and the more healthcare service organizations, such as hospitals, provide health information on the social media. On the one hand, some medical research examine the effect of social media as a treatment tool, on the other hand, social research or health informatics research describe these social media use phenomenon. However, little empirical research has systematically examined the causal relationship considering the social media environment and the process of social media impact to health outcome. To fill this gap, this study investigated how social media influence on individual user's health outcome using the SPO framework, especially focusing on their self-management outcome. The result shows that Health Information Social Media (HISM) significantly influence on one's psychological, behavioral, and physical health outcome. And, Source Credibility and Experience Base Health Information have significant influence over the influence.