Dormagen (German pronunciation: [ˈdɔʁmaːɡn̩] ⓘ; Ripuarian: Dormaje) is a town in North Rhine-Westphalia, Germany in the Rhein-Kreis Neuss.

Dormagen is situated between Düsseldorf – Cologne – Mönchengladbach on the western bank of the river Rhine.

Its main industry and employer is the chemical factory of Bayer AG and since its founding the Covestro AG.

The town has three stations (Dormagen, Nievenheim and Dormagen Chempark) on the Lower Left Rhine Railway, linking Cologne and Krefeld.

The German motorway 57 connects Dormagen with the same cities.