Plasnewydd (meaning New Manor or New Place) is an electoral ward (and formerly the name of a community) of Cardiff, Wales.

It is bounded by the electoral wards of Cyncoed (Roath Park) to the north; Penylan to the northeast; Adamsdown (main Newport Road) to the southwest; and Cathays (Cardiff to Caerphilly railway) to the west.

[1] Plasnewydd takes its name from a 17th century house called "The New Place", originally a home of Edwards Richard and, in 1890, given to the local people.

[2] Plasnewydd was previously the name of the Roath community until the Boundary Commission renamed it in the 2010s.

[3] Plasnewydd ward elects four councillors to sit on Cardiff Council.