In 1939, Beriev was ordered to develop a successor to the KOR-1 design, which would overcome the numerous problems encountered in operational experience with that design. The new aircraft, with the in-house designation KOR-2, first flew on 21 October 1940 at the Beriev factory in Taganrog.
Testing continued through January 1941, when series production was ordered under the designation Be-4, at a factory near Moscow. However, due to the start of World War II, only two aircraft were completed. The factory was dismantled, and evacuated to Omsk, then to Krasnoyarsk, where production resumed in May 1943 through the end of 1945. A total of 47 aircraft were eventually completed.
The Be-4 was placed into operational service with the Russian Black Sea Fleet from 1942, where it was used for coastal reconnaissance, anti submarine and transport duties. It was also used on the cruisers Maxim Gorki and Kirov.