Barrhaven is a rapidly growing suburban neighbourhood in the southwest of the urban area of the city of Ottawa, Ontario, Canada, about 17 km (11 mi) southwest of downtown Ottawa. Prior to amalgamation with Ottawa in 2001, Barrhaven was part of the City of Nepean. Its population as of the Canada 2011 Census was 72,324.

Barrhaven is approximately bounded to the north by the Greenbelt, to the east by the Rideau River, to the west by Highway 416, and to the south by the new Half Moon Bay development along Cambrian Road south of the Jock River.

Riverside South is just west across the Rideau River. Directly south of Barrhaven is the village of Manotick.

Modern Barrhaven was established in the 1960s, one of a group of new suburbs built outside the Greenbelt from the main city of Ottawa. Building in the area was begun by Mel Barr, for whom the community is named. Barr had originally purchased a 200 acre farm with the intent of constructing a horse racing track. However the Rideau Carleton Raceway was built further to the east and Barr instead decided to develop his land for housing.

Modern Barrhaven consists of town homes mixed with streets having comparatively large suburban single homes.

Barrhaven subsequently grew rapidly into a community of several tens of thousands of people. Commercial centres were slower to arrive. The vast Barrhaven Town Centre complex opened in 1991 with big box stores and smaller commercial establishments, as well as a few smaller shopping malls. The area got its first high school in 1998 when Mother Teresa High School (Catholic) opened, followed by John McCrae Secondary School (public) in 1999. Barrhaven gained its third high school in 2002 when St. Joseph High School (Catholic) opened. In September 2009, Longfields-Davidson Heights Secondary School (Public) opened.

The Main areas in Barrhaven are Old Barrhaven, Longfields, Chapman Mills, Hearts Desire, Stonebridge, Barrhaven on the Green and Half Moon Bay.

Amenities in Barrhaven include the Walter Baker Sports Centre, the new Minto Recreation Complex, Market Place shopping plus the Via Rail station at Fallowfield and Woodroffe.

Eating out has a variety of tastes and experiences. There is a choice of  Heart a& Crown, Broadway Bar and Grill, Boston Pizza, Swiss Chalet, Kelsey's, The Royal Oak and The Barley Mow.