A Katzbalger (German: [ˈkat͡sbalɡɐ] ⓘ) is a short arming sword, used in early modern Europe notable for its sturdy build and a distinctive s-shaped or figure-8 shaped guard.

Measuring 70–80 cm (28–31 in) long and weighing 0.8–1.5 kg (1.8–3.3 lb), it was the signature blade of the Landsknecht.

The katzbalger is a side-arm, often used by pikemen, archers, and crossbowmen as a last resort if the enemy were to draw too close for bows or pikes to be effective.

As with many sword varieties, variations exist within the type and katzbalger-style hilts can be found paired with slimmer and more thrust-oriented blades.

Another theory is that the word derives from balgen (brawling), and refers to intense, close-quarter combat like fights between feral cats.