As online learning and teaching are becoming an educational trend, online students’ engagement will directly impact the learning and teaching effects and outcomes. A scientific application of gamification in online learning, teaching, and online course design will improve online learners’ learning experience and help build a better virtual learning context for online learners worldwide. This study focuses on how gamification can engage online students from skills, emotional, participation, and performance perspectives. A mixed method has been applied to further explore the relationships between gamification components and online students’ engagement and how online students perceive the impacts of gamification on their online learning experience. This study extended the research about the gamification mechanics that foster online learner engagement and offered guidelines for future online course design and development.