Abstract
This paper develops an interactive multimedia on the thermodynamic concept with the main purpose to examine its implication on physics teaching with problem-based learning model. This research was conducted in three stages, namely preliminary study, development stage, and field testing stage. The validator has validated the interactive multimedia. The testing phase used one group pretest&post-test design. The instrument used to measure mastery of concepts is a question about each concept of thermodynamics. The results showed that the average students' concepts mastery in the sub-material of the second law of thermodynamics was higher than that of other sub-materials. In general, an increase in students' mastery of thermodynamics concepts was in the medium category. This shows that interactive multimedia in problem-based learning succeeded in increasing students' mastery of thermodynamic concepts.