The Berdan rifle is a single-shot rifle created by American engineer and inventor Hiram Berdan in 1868. It was the service rifle of the Imperial Russian Army from 1870 to 1891, when replaced by the Mosin–Nagant rifle. The gun was widely used in Russia as a hunting weapon, and sporting variants, including shotguns, were produced until the mid-1930s. The Russian Berdan I (M1868) and Berdan II (M1870) rifles of .42 caliber are distinct from the Spanish Berdan 15 mm (0.591 in) conversion rifles adopted by Spain as the M1857/67 Berdan.

In firearm designs, the term single-shot refers to guns that can hold only a single round of ammunition inside and thus must be reloaded manually after every shot. Compared to multi-shot repeating firearms ("repeaters"), single-shot designs have no moving parts other than the trigger, hammer/firing pin or frizzen, and therefore do not need a sizable receiver behind the barrel to accommodate a moving action, making them far less complex and more robust than revolvers or magazine/belt-fed firearms, but also with much slower rates of fire.