Gatineau is the fourth largest city in Québec (Canada). It is situated in the southwestern part of the province, on the northern bank of the Ottawa River. At least 87 species of dragonfly have been recorded in Gatineau, and surveys conducted in the city in 2012 and 2013 documented the frequency, relative abundance and breeding of 82 of these. A comparison with historical data for the period from 1886 to 1935, showed that at least 90 % of the species recorded have maintained their presence in the city since the beginning of the 20th century. However, 8 species associated with streams, rivers or temporary wetlands, may have declined or disappeared. By contrast, at least 7 generalist species associated with still water bodies, are expanding in Gatineau. With the exception of one species from the family Coenagrionidae, these are all from the family Libellulidae. These changes in the dragonfly community are likely due to urban sprawl. Dragonflies, which are useful bio-indicators of environmental changes occurring in wetlands, can be easily observed and monitored through citizen science projects.