Béarnese (endonym bearnés or biarnés; French: béarnais [beaʁnɛ] ^ⓘ) is the variety of Gascon spoken in Béarn.

The usage of a specific name for Béarnese lies in the history of Béarn, a viscounty that became a sovereign principality under Gaston Fébus. From the middle of the 13th century until the French Revolution, Béarnese was the institutional language of this territory. The standardised orthography defined by the administrative and judicial acts was adopted outside the limits of Béarn, not only in a part of Gascony, but also in some Basque territories.

The French language exerted an increasing influence on Béarn from the middle of the 16th century, due to its annexation as a French province in 1620. The use of Béarnese as an institutional language ended with the Revolution, its use being limited to popular culture. Cyprien Despourrins, Xavier Navarrot and Alexis Peyret, for example, used Béarnese in their works. From the second half of the 19th century to the first half of the 20th century, the Béarnese language was standardized, particularly by Vastin Lespy, Simin Palay and Jean Bouzet.

Béarnese remained the majority language among the Bearnais people in the 18th century. It was not until the second half of the 19th century that its use declined in favor of French. The French school entered into direct conflict with the use of regional languages in the last third of the nineteenth century and until the first half of the twentieth century, causing a clear decline in the transmission of Béarnais within the families from the 1950s. As a reaction, the first calandreta school was created in Pau in 1980, allowing for the revival of its teaching. The number of speakers of Béarnais is difficult to estimate; a 2008 survey suggests that 8 to 15% of the population speaks Béarnese, depending on the definition chosen.

The word Béarnese comes from the endonym bearnés or biarnés. The term derives directly from the people of Venarni, or Benearni, who gave their name to Béarn. The city of the Venarni, Beneharnum, was included in Novempopulania at the beginning of the 5th century. The origin of the name of the Béarnese has several hypotheses, one of which evokes a relationship with the Basque word behera which means "below". Although used from the middle of the 13th century in the administration of the principality, the use of Béarnese did not benefit from a "mystique" of the language, as in the kingdom of France. The linguistic conscience is not affirmed, the language never being named in the writings. The term "Béarnese" appears for the first time in the French language, but it is not used in the French language. The term Béarnese appears for the first time in the writings in a document of March 1, 1533, the States of Béarn refuse to examine texts written in French, and require their translation into Béarnes. In 1556, Jeanne d'Albret also gave reason to the States which claimed the exclusive use of bearnes for any pleading and writing of justice. Arnaud de Salette is considered to be the first writer to claim a writing in rima bernesa in his translation of the Genevan Psalter, composed between 1568 and 1571 and published in 1583 in Orthez.

The use of the name "Béarnese" continued in the following centuries, as with Jean-Henri Fondeville in his eglogues of the end of the seventeenth century, who expresses: "En frances, en biarnes, chens nat mout de latii." In the late nineteenth century, the use of the word "Béarnese" to designate the language of Béarn was gradually replaced by the word patois, with its pejorative aspect. This movement is common to the whole of France. The use of the term patois declined from the 1980s onwards, with the revival of regional languages. At the same time, the use of the name "Occitan" increased with the rise of Occitanism. During the sociolinguistic survey commissioned by the Conseil départemental des Pyrénées-Atlantiques in 2018, the people of Béarn were asked about the name they gave to their regional language. The term "Béarnese" obtained between 62 per cent and 70 per cent of the votes depending on the intercommunity concerned, compared to 19% to 31% for the term "patois", 8 to 14 per cent for "Occitan" and a maximum of 3 per cent for "Gascon".

The expression "Béarnese language" was used as early as Arnaud de Salette in the 16th century, "la lengoa bernesa", and this use is not based on a scientific observation, but on an identity approach, in a context of rising Béarn nationalism. The expression langue béarnaise continues to be regularly used thereafter, a use that is now historical, but still not scientific.

In the village of Aas, Pyrénées-Atlantiques, shepherds maintained a whistled language until the 20th century. According to Graham Robb, very few outsiders knew of the language until a 1959 TV program mentioned it. Whistles were up to 100 decibels, and were used for communication by shepherds in the mountains and by women working in the fields. During the Nazi occupation of World War II, the language was used to ferry refugees across the France–Spain border.