Haruhiko Mitsunaga (born 1979) is a Japanese educational psychologist and Associate Professor at the Graduate School of Education and Human Development, Nagoya University. His research specializes in psychometrics, educational measurement, and test theory, with particular emphasis on item response theory (IRT) and its application to educational testing and psychological assessment. Before joining Nagoya University, he worked at the National Personnel Authority and taught at Shimane University. Through his research and writing, Mitsunaga examines how tests measure human abilities and academic achievement, how assessment results should be interpreted, and how fair and reliable evaluation systems can be developed for education and entrance examinations.