In line with the increasing significance of technology today, the use of digital technology in digital forensic investigation has increased as well. The effect is that many investigations that require the expertise of digital forensics are unable be completed timely by law enforcement agencies around the world. Being consistent with the use of online social media which is the focus of the world nowadays, too many incidents of digital and physical crime have been linked to it. Therefore, a digital forensic model specifically for online social networks needs to be developed to obtain the best evidence and investigation results. A literature review related to digital forensic, models that have been developed in digital forensic and online social network has been conducted in this study. The results found that most studies involve general investigations and processes that overlap with each other. Moreover, there is no model yet to formulate a systemic investigation in the online social network. To overcome this problem, we have developed a standard model for digital forensic investigation of online social networks in this study. This model combines some of the models that have been developed before and added some new activities that are appropriate to the investigation.