The asp (Leuciscus aspius) is a European freshwater fish of the Cyprinidae family.

They tend to be active during the evening, when they may create large splashes as they hunt near the surface of the water.

Asps can be found in Estonia, Lithuania, Latvia, Germany, Norway, Sweden, Finland, the Czech Republic, Poland, Ukraine, Bulgaria, Romania, Russia, Switzerland, Slovenia, the Netherlands, and Belgium.

In Switzerland, asps have migrated through the Rhine–Main–Danube Canal, as in Serbia, Croatia, Austria, Hungary, and Slovakia.

In the eastern regions of Europe, it is a common species in flowing waters, and popular for fly and other types of fishing.