As the use of online learning has continued to expand, there has been a growing demand for advanced software or social sites that can enhance learning outcomes in online settings. It is important to explore how learner-learner, learner-teacher and learner-content interactions affect on learning outcomes while using the social sites such as Facebook, Twitter, WeChat, Blogs, etc. Although some prior research highlight that there is a demand for interaction in online courses, specific design tactics and empirical evaluation of the effects of interaction on learning outcomes in blog-based courses are lacking. Thus, a blog learning platform named "Learner's Digest Blog" (LDB) was developed to facilitate the three types of interactions and enhance learning outcomes. A total of 26 learners participated in the blog-based interactive learning environment. The study addressed two research questions, and regression analysis was used to analyze the data. The findings indicated a significant influence between learner-learner interaction, learner-teacher interaction and learner-content interaction on subjective learning outcome. In contrast, there was no significant influence of learner-teacher interaction on objective learning outcomes, but learner-learner and learner-content did significantly affect objective learning outcomes. A significant relationship was also found between students' subjective and objective learning outcomes.