Benjamin Franklin Isherwood (October 6, 1822 – June 19, 1915) was an engineering officer in the United States Navy during the early days of steam-powered warships.

When the Mexican–American War ended, Isherwood was assigned to the Washington Navy Yard, where he assisted Charles Stuart in designing engines and experiments with steam as a source of power for propelling ships.

Throughout the 1850s, Isherwood compiled operational and performance data from steam engines in American and foreign commercial vessels and warships.

Isherwood went to sea during the period between the wars, serving as Chief Engineer of the steam frigate San Jacinto on a cruise of more than three years on the Asiatic Station.

Shortly after the outbreak of the Civil War, Isherwood was appointed Engineer-in-Chief of the Navy, and so important were his services considered that the Bureau of Steam Engineering was created under his direction.

Immediately upon the conclusion of the war, Isherwood was principally involved with organizing a new scientific curriculum for steam engineering at the United States Naval Academy at Annapolis.

After the presidential inauguration of Ulysses S. Grant, Isherwood's longtime patron, Secretary of the Navy Gideon Welles, could no longer protect him.

Following a tour of European dockyards, he became president of the Experimental Board under the Bureau of Steam Engineering until his retirement as a commodore on October 6, 1884.

Isherwood Hall, built in 1905 on the campus of the United States Naval Academy, was the home of the Department of Marine Engineering.