| Country: | DEU |
| Type: | A |
| Route: | 23 |
| Map: | Bundesautobahn 23 map.png |
| Length Km: | 96 |
| Direction A: | North |
| Direction B: | South |
| Terminus A: | B 5 in Heide |
| Terminus B: | A 7 in Hamburg |
| Previous Type: | A |
| Previous Route: | 21 |
| Next Type: | A |
| Next Route: | 24 |
| States: | Schleswig-Holstein, Hamburg |
is an autobahn in Germany. It runs largely parallel to the Bundesstraße 5; its main purpose is to connect the hinterland of Hamburg. North of Heide, the A 23 becomes B 5 and connects Eiderstedt, Husum and the ferries to the islands of Nordfriesland to the autobahn network.