Katsuhiko Ohnuma(大沼克彦) (born 1944) is a Japanese prehistorian and lithic expert.

He was director of the Institute for Cultural Studies of Ancient Iraq, Kokushikan University .

Ohnuma received his Ph.D in 1982 from the University of London, and has led several archeological projects, including rescue excavations in Syria and Iraq, focusing mainly on Neolithic and later sites.

His other research activities include publishing a book on the Lebanese Ksar Akil rockshelter[1] in British archaeological reports series and numerous articles.

Taking a focused approach to various problems as outlined above, he developed effective experiments to test his hypotheses and elucidate aspects of the behavior of prehistoric populations.