Rosny is a suburb of the City of Clarence, part of the greater Hobart area, Tasmania, Australia. It is located on the eastern shore of the Derwent River, between the suburbs of Montagu Bay and Rosny Park, approximately 4 kilometres from Hobart's centre. Rosny is the residential part of its commercial namesake Rosny Park.
Rosny is a pretty, quiet, residential area, with sweeping views of the Derwent River and its estuary, the Tasman Bridge and Mount Wellington, and looks directly across the river to the CBD of Hobart. It is located on a narrow peninsula which juts out from the eastern shore at Rosny Point and climbs the rising slopes of Rosny Hill.