Zelzate is a municipality located in the Belgian province of East Flanders. The municipality only comprises the town of Zelzate proper. On January 1, 2006, Zelzate had a total population of 12,176. The total area is 13.71 km² which gives a population density of 888 inhabitants per km².
Zelzate is divided into two parts by the Ghent-Terneuzen Canal. There is a concrete drawbridge and a tunnel to connect the two sides. Zelzate is known for the nearby polluting industry, which makes it the village with the lowest air quality in the country. Recently ArcelorMittal Ghent (Sidmar) made a major investment which resulted in an emission decrease of 90%.