This study aimed to determine the effects of art-based chemistry activities (ABCA) on high school students' conceptual understanding in chemistry. The study used the pretest-posttest control group design. A total of 64 third-year high school students from two different chemistry classes participated in the study. One class was exposed to art-based chemistry activities (ABCA), while the other group was taught using non-art-based activities (NABA). Research data were obtained through the chemistry concept understanding test (CCUT), an instrument specifically developed for this study. Data analyses revealed a significant difference between the mean posttest scores in the CCUT of both groups, with the mean posttest scores of the ABCA group higher than the mean posttest scores of the NABA group. Moreover, ABCA students showed best understanding of the concepts in 63% (5 of 8) of the modified multiple-choice items of the CCUT. The positive effect of the intervention on the concept understanding of students in chemistry stemmed from the creation and display of chemistry artwork by the ABCA group in the activities. The opportunities for the ABCA group communicating their knowledge of chemistry through their creation of a chemistry artwork contributed to their concept understanding in chemistry. The art-based chemistry activities positively affected students' conceptual understanding in chemistry. (Contains 3 tables.)