This descriptive content analysis study was carried out to review students and pre-service teachers ' mental model of chemistry concepts. This study was motivated by difficulties experienced by students and teachers in the process of learning chemistry. This study put on criteria with specific keyword about a mental model in chemistry concepts and a period of 2009 till 2019 which relevant databases yielded a total of 66 articles. This study covers 41 qualitative studies, 18 quantitative studies, and this remains mix method studies. Article ' s aspects focused on such parameters as aim, method, sample, data collection tool, data analysis, chemistry concept, mental model theory, and recommendation of studies. Using content analysis, as a result was known that most studies used qualitative methods with a variety of data collection tools and data analysis techniques. Moreover, these mental models studies were mostly involved students who learned inorganic chemistry. General conclusions from this study in the importance form of the mental model exploration to master the chemistry concepts and this is intended to improve the chemistry learning process. This research also implies to do good innovative changes in various aspects to improve their scientific mental model. These changes include to innovate classroom practices, further researches, curriculum policy, and learning media developer.