This study aims to develop a four-tiered misconception diagnostic assessment to reveal the profile of engineering students' conceptual understanding. This research is a development research (R & D). The research sample was students of the electrical engineering study program at the Politeknik Muhammadiyah Tegal. Data analysis consisted of expert validation test, readability test, and large-scale test. The results of the expert validation test obtained that the instrument was suitable for use. The results of the readability test obtained that the level of legibility and clarity of sentences and pictures was good. The results of the large-scale test obtained that eight questions were declared valid. The results of the reliability test obtained the value of Cronbach's Alpha = 0.858, so the instrument is reliable. The results of the student's concept understanding test were obtained as many as 21.4% of students understood the concept, 14.2% understood the concept, but were not sure, 13.7% understood partly, 26% did not understand the concept, and 27.9% had misconceptions. The biggest misconception finding is that students think that the electric current that passes through the branch closest to the voltage source has the greatest value.