Chemistry is a subject area that is difficult to understand for some students as it contains abstract concepts, such as mole, molecule and particle. The mole concept is one of the most important topics in which students have difficulty in understanding. There are many studies in the literature on the mole concept. Students who do not fully understand the mole experience difficulties in understanding the subsequent topics. Especially, results can be often incorrect in stoichiometry problems since the calculations revolve around the mole concept. The purpose of this study was to determine the effectiveness of using conceptual change strategy in teaching the mole concept to freshman general chemistry students. A pretest-posttest control group experimental model was used. The control group was lectured via traditional teaching method while conceptual change texts were used to teach the mole concept to the experimental group. An achievement test of multiple-choice questions was developed to gather data from both groups as pre and posttest. Analysis of the data was performed by using SPSS (Statistical Package for Social Sciences) software. The results demonstrated that the use of conceptual change method was more effective in promoting understanding of the mole concept compared to the traditional method. Developing similar teaching materials for conceptual change to improve teaching effectiveness and student success in the other topics of chemistry may be an effective approach