Hamoaze House is a large detached house in Mount Wise, Devonport, Plymouth, built in 1795 as the home of the Commander-in-Chief, Plymouth. It should not be confused with the earlier Admiralty House, Mount Wise (originally known as Government House), built 1789-93 as the home of the military Governor of Plymouth.

It is listed Grade II on the National Heritage List for England.^[1]

The house was built in 1795 by Charles Lennox, 3rd Duke of Richmond (1735-1806), elder brother of Lord George Lennox (1737-1805), Governor of Plymouth (1784-1805), and served as the home of the Commander-in-Chief, Plymouth from 1809 until 1934 when that officer moved to Government House.^[2] It is named after the Hamoaze which is the tidal estuary of the River Tamar.^[3] It became the home of the General Officer Commanding the Plymouth Division of the Royal Marines later in 1934.^[4] Plymouth Development Corporation marketed the building and arranged its sale to a charitable trust in 1998^[5] and it has since become a centre for drug and alcohol rehabilitation.^[6]