The low learning outcomes of students in science are caused by teacher-centered learning and limited practical activities that cause students to lack a deep understanding of the concept. Energy and its changes require exploration and experimentation activities so that students are able to understand the concept concretely, but limited laboratory facilities become an obstacle in the learning process. This study aims to determine the effect of the discovery learning model assisted by the PhET virtual laboratory media on the learning outcomes of sixth-grade students of SD Negeri 54 Banda Aceh. This study uses a quantitative approach with a quasi-experimental research type using a Non-Equivalent Control Group Design. The study population was all sixth-grade students of SD Negeri 54 Banda Aceh with samples of class VI-B as the control class and class VI-C as the experimental class. Data collection techniques were carried out through learning outcome tests in the form of pretests and posttests. Data analysis used the N-Gain test, normality test, and hypothesis testing using the Mann-Whitney U test. The results showed that student learning outcomes in the experimental class were higher than those in the control class. Based on the results of the Mann-Whitney U test, a significance value of 0.001 < 0.05 was obtained, so H_a was accepted and H_0 was rejected. It can be concluded that there is an influence of the discovery learning model assisted by the PhET virtual laboratory media on student learning outcomes in the material on energy and its changes in class VI of SD Negeri 54 Banda Aceh.