J.C.M. Warnsinck (11 November 1882, Hoogwoud, North Holland - 21 July 1943, The Hague) was a Dutch naval officer and naval historian. Johan Carel Marinus Warnsinck was the son of the notary Cornelis Warnsinck and his wife, Tettje Halbertsma. He entered the Royal Naval Academy at Den Helder in 1899 and was commissioned an officer in the Royal Netherlands Navy in 1903, eventually rising to the rank of captain in 1930. In 1919, he married Catarina Elisabeth Delprat and they had one son and a daughter. He saw naval service in the East and West Indies as well as in European waters. In the Royal Netherlands Navy, he was a hydrographic specialist. From about 1920, he began to be interested in naval history and began with a special interest in the three Anglo-Dutch wars (1652-1674). He retired from active service in 1932 and devoted the remainder of his life to the study of Dutch maritime history.
Warnsinck became a key pioneer for the academic study of maritime history in The Netherlands. In 1933, he was appointed a lecturer at the University of Amsterdam and additionally at Leiden University in 1937. In 1939, he became Professor of Maritime History at the University of Utrecht. For many years, he was on the Council of the Linschoten Society and Secretary of the Commission for maritime history of the Royal Academy of Science. In 1938, he was elected an associate member of the Académie de Marine in Paris.