Prisons in Germany are a set of penal institutions in the Federal Republic of Germany. Their purpose is rehabilitation--to enable prisoners to lead a life of "social responsibility without committing criminal offenses" upon release--and public safety. Prisons are administered by each federal state, but governed by an overarching federal law. There are 183 prisons in all, with the most located in Germany's most populous states Bavaria and North Rhine-Westphalia. In 2023, the total number of prisoners in Germany including pre-trial detainees was 57,955, an incarceration rate of 68 per 100,000 people.

Prisoners in Germany are given different freedoms and responsibilities. Most prisoners are obligated to perform paid work in an effort to promote resocialization efforts. Often, prisoners have television, posters hanging in their cells, private bathrooms, and free time in which they can roam around outside their cells. These conditions, along with the focus on rehabilitation, have resulted in advocates using German prisons as an example for improvement to prison conditions in other parts of the world.

The roots of German prison legislation lie in the "Basic Law" (Grundgesetz), which originated as the constitutional framework for West Germany immediately following the Second World War. The Basic Law enumerates a set of basic principles, including the inviolability of human dignity and a commitment to the rule of law. In Germany, the Federal Constitutional Court is responsible for the enforcement of the Basic Law, and the rights detailed within it cannot be abolished and can only be restricted or amended by primary legislation.

Before 1970, there were five kinds of confinement in Germany. They were Zuchthaus (hard labor prison), Gefängnis (prison), Einschließung (jail), Arbeitshaus (workhouse), and Haft (custody). A Zuchthaus was a prison of physically exerting hard labor, such as breaking rocks, where prisoners had to work, even to the point of collapse. This was repealed by the Große Strafrechtsreform ("Great Panel Law Reform") of the West German penal code, which came into force on April 1, 1970. Today, a Gefängnis is known as a Justizvollzugsanstalt, or "Justice Enforcement Facility".

Until the 1970s, prisoners in Germany were considered to have a "special authority relationship" (besonderes Gewaltverhältnis) with the German state, and their rights could therefore be restricted without the need for primary legislation. However, in 1972, the Federal Constitutional Court rejected this idea, and ruled that prisons must be legislatively regulated. The court ruled further in 1973 that it is constitutionally required that prison sentences have a primary goal of resocializing offenders.

In response, the first German Prison Act was passed in 1976 by federal legislators in accordance with these requirements. In response to a third Federal Constitutional Court ruling in May 2006, a legal basis for juvenile detention was also required to be established by the end of 2007.

In an unrelated development, the Federal German parliament decided in 2006 to reorganize relations between the Federal government and the Länder (states) ("federalism reform"). As part of this reform, the responsibility for prison legislation was assigned to the individual Länder. All 16 Länder have their own prison legislation, many of which are based on a Model Prison Act adopted August 23, 2011 by the Länder ministers of justice. The 1976 federal legislation remains in force for regulatory areas not covered by Länder laws.

As of 2021, there are several forms of detention in the German penal system.