Sagamore Hill Military Reservation was a coastal defense site located in Sagamore Beach, Massachusetts.

Today, the site is the location of Scusset Beach State Reservation.

Sagamore Hill Military Reservation was built on state land in 1941-1942 by Battery C, 241st Coast Artillery Regiment of the Massachusetts National Guard, beginning shortly after the attack on Pearl Harbor in December 1941.

Its mission was to protect the northern terminus of the Cape Cod Canal from possible naval attack; it was mirrored at the southern entrance by Butler Point Military Reservation.

The site had two "Panama mounts" (circular concrete platforms) for two towed 155 mm guns.