Kashi Prasad Jayaswal Research Institute is a research institute in Patna, Bihar and headquartered at Patna Museum Building.
It was established in October 1950 by the Government of Bihar. It was named after Kashi Prasad Jayaswal, an Indian Historian and lawyer. It is currently working under the Directorship of Kumari Lalita. It has published many books in Hindi and English language.