Frogner is a residential and retail borough in the West End of Oslo, Norway, with a population of 59,269 as of 2020. In addition to the original Frogner, the borough incorporates Bygdøy, Uranienborg and Majorstuen. The borough is named after Frogner Manor, and includes Frogner Park. The borough has the highest real estate prices in Norway.

The East End and West End are used as names for the two parts of Oslo, Norway, formed by the economic and socially segregating separation line that has historically passed along the street Uelands gate. The Akerselva river is often seen as a boundary between west and east, but that can be misleading, as there are working-class neighbourhoods on both sides of the river.