Manotick (/ˈmænətɪk/ MAN-ə-tik) is a community in Rideau-Jock Ward in the rural south part of the City of Ottawa, Ontario, Canada. It is a suburb of the city, located on the Rideau River, immediately south of the suburbs Barrhaven and Riverside South, about 25 km (16 mi) from downtown Ottawa. It was founded by Moss Kent Dickinson in 1864. He named the village 'Manotick', after the Algonquin word for 'island'. It has been part of the City of Ottawa since amalgamation in 2001. Prior to that, it was located in Rideau Township. According to the 2021 Canadian Census, Manotick had a population of 5,315.

The village of Long Island Locks was first settled in 1833. In the 1830s, a small settlement formed in the area of the newly constructed Long Island locks on the Rideau Canal, but there was no development in the area of present-day Manotick. A post office was established in 1854.

In 1859, when a bulkhead was constructed across the west branch of the Rideau River, the entrepreneur Moss Kent Dickinson and his partner Joseph Merrill Currier obtained the water rights and constructed a stone mill on the shores of the Rideau River. The flour mill, as well as a carding mill, sawmill and a bung factory, also built by Dickinson, helped spur the development of the settlement. The flour mill was purchased in 1946 by Harry Watson and renamed Watson's Mill. It survives as a working museum, with an operational grist mill.

M. K. Dickinson, Esq., established the Long Island Flouring Mills in 1860, which had the capacity of grinding one hundred barrels of flour per diem. The buildings were substantially built of stone. The saw mill, built by M. K. Dickinson, Esq., employed twelve men and turned out about two million feet of sawn lumber per annum.

Dickinson House, built in 1863, was the first major building in Manotick. It served as a general store, bank, post office, and telegraph office. The Dickinson, Spratt, and Watson families, which owned and operated Watson’s Mill, used the house as their residence from 1870 to 1972. It is currently furnished to give visitors an interpretation of what the space was like when the Dickinson family was in residence. It is included amongst other architecturally interesting and historically significant buildings in Doors Open Ottawa, alongside Watson's Mill. Open Doors Ottawa sometimes coincides with Dickinson Days, which is Manotick’s annual festival celebrating the Founder of the village.

By 1866, Long Island Locks was a post village with a population of 100 of the township of Gloucester, on the Rideau Canal, seven miles from Gloucester station, on the Ottawa and Prescott railway, and 15 miles from Ottawa. The village contained two general stores and a number of mechanics. There were two church buildings here, one occupied alternately by the Presbyterian congregation and the English Church, and the other by the Wesleyan Methodists.

By 1866, Manotick was a post village with a population of 100 of the township of North Gower, on the Rideau River, five miles from Kelly's station on the Ottawa and Prescott Railway, and 17 miles from Ottawa. There was excellent water power supplied by the Rideau Canal with mails tri-weekly. The Loyal Orange Lodge, No. 477, met in Orange Hall in the village on the first Friday in each month.

The original St. James Anglican Church was built of wood in a Norman style in 1876 on land donated by Moss Kent Dickinson. When a larger church was built in 1985, the original style and appearance, including a Norman tower, the original stained glass windows, plaques and much of the other furnishings were maintained. The church was included with other architecturally interesting and historically-significant buildings in Doors Open Ottawa, held June 2 and 3, 2012.