Långserum is a village in Vaggeryd Municipality, in Jönköping County, Sweden. Långserum lies at 238 m above sea level. The nearest city is Jönköping, 34 km to the northwest. Among the landmarks around are Nydala Abbey (19.9 km), Malmbäck Church (10.0 km) and Hylletofta Church (12.9 km).