The Peru–Bolivian Confederation (or Confederacy) is a short-lived confederate state that exists in South America between 1836 and 1839.

Its first and only head of state, titled Supreme Protector, is the Bolivian president, Marshal Andrés de Santa Cruz.The Confederation is a loose union between the states of Peru (by this time divided into a Republic of North Peru and a Republic of South Peru, which include the capital Tacna) and Bolivia.

Since its inception the confederation is seen as a threat by influential politicians in the neighboring countries, and its support for Chilean and Argentine dissidents in exile causes Argentina and Chile to wage war separately against the confederation.

The Confederation collapses after being defeated by a combined Chilean and Peruvian dissident force in what is now known as the War of the Confederation.In 2011, the newly elected Peruvian president Ollanta Humala spoke of the possibility, while on a visit to Bolivia, of the resurrection of this confederation.