Horizontal education-job mismatch is a phenomenon that is commonplace in the Indonesian workforce. A worker carries out work in a different domain from his educational background. The aim of this research is to determine the dynamics of work engagement in workers who experience horizontal education-job mismatch. This research uses a qualitative method with a phenomenological approach. Sampling was carried out using purposive sampling. The respondents of this research were three workers who were working outside their educational background (mismatch). Research data collection used blank life histories, interviews and observations. Research data analysis uses Interpretative Phenomenology Analysis (IPA), is a detailed examination technique of the experiences in an individual's life. The research results show that the three respondents FM, NA and AN have good work engagement, with indicators of vigor, dedication and absorption in work. All respondents were able to adapt well and show good performance in various ways, namely by learning by doing, attending training, asking friends or superiors. The company also has an important role in forming employee work engagement.​