Jun Aruga was born in Tokyo, Japan, in 1962. He graduated from the School of Medicine at Tohoku University in 1987, and obtained his PhD in 1991 from the same institution. After two years as assistant professor at the Institute of Medical Science, University of Tokyo, he joined RIKEN as a research scientist in the Tsukuba Life Science Centre.
He moved to the RIKEN Brain Science Institute in 1999 and was promoted to laboratory head in 2004. Since then, he has acted as director of his own research group. His research focuses on developmental and behavioural neurobiology based on comparative genomics and analysis of neurological disorder model animals.