Ljungby is a former parish in Falkenberg Municipality, Halland County, Sweden. The name is most likely derived from the conjunction of ljung (Calluna) and by (village). It is confirmed in written sources from at least 1267. Two conurbations exist within the parish borders; Ljungby/Lilla Ljungby and Bergagård. A minor part of Ätrafors is also within the parish boundary.