Nørre Alslev is a town with a population of 2,384 (1 January 2012) on the northern end of the island of Falster in south Denmark. It belongs to Guldborgsund municipality in Region Sjælland.
Until January 1, 2007 Nørre Alslev was also a municipality (Danish, kommune) in the former Storstrøm County. The municipality covered an area of 181 km², and had a total population of 9,595 (2005). Its last mayor was Niels Larsen, a member of the Venstre (Liberal Party) political party. Nørre Alslev municipality ceased to exist as the result of Kommunalreformen ("The Municipality Reform" of 2007). It was merged with Nykøbing Falster, Nysted, Sakskøbing, Stubbekøbing, and Sydfalster municipalities to form the new Guldborgsund municipality.
Two bridges connect the former municipality, and the rest of Falster, to Zealand. The 3,199 meter long Storstrøm Bridge connects the former municipality from near the town of Orehoved to Masnedø, an island in Storstrømmen, and the 201 meter long Masnedsund Bridge (Masnedsundbroen) continues from there to the town of Vordingborg. The Storstrøm Bridge supports two lanes of traffic, plus a single track of railroad. This vital railroad line leads to train ferry service in the town of Rødby Færge in south Lolland to Puttgarden, Germany over the Femern Belt. Both of these bridges were inaugurated in 1937.
Further to the east are the two Farø Bridges (the 1,726 meter long Farø High Bridge and the 1,596 meter long Farø Low Bridge) which opened in 1985.