The Reinheitsgebot is a regulation about the purity of beer. The regulation started in Ingolstadt, in Bavaria, in Germany, in 1516.

The regulation says several things:

• It says what can be part of beer, and what can not. Beer may only contain water, barley, and hops.
• It gives a price to beer. This is important for taxation. The price is set to 1-2 Pfennigs per Maß.

Some people talk about the Bavarian Reinheitsgebot, or the German Reinheitsgebot. They all mean the same thing. There are similar acts in the other states which later became known as Germany.