Several proposed critical success factors (CSF's) of Knowledge Sharing activity in Online Community has been determined based on Literature Review using PRISMA method. There are 18 CSF's identified from 22 papers from academic database in Scopus, IEEE Xplore, and Science Direct that have been through 4 screening phases. We validated the proposed CSF's by using validate test and reliability test based on questionnaires. The questionnaire distributed to respondents who actively joined in online community. We had 18 CSF's that were valid after conducting validation testing. Then, we conduct the reliability testing to determine whether the instrument is reliable or not. From the indicators that have been obtained, it can be concluded that the success of Knowledge Sharing in online community influenced by individual-related, social-related, community-related, and IT-related which consist of 18 key factors. The findings of this study can help a better understanding of knowledge sharing in online community to improve knowledge contribution in online community.