The Baetic System or Betic System (Spanish: Sistema Bético) is one of the main systems of mountain ranges in Spain. Located in the southern and eastern Iberian Peninsula, it is also known as the Cordilleras Béticas (Baetic Mountain Ranges) or Baetic Mountains. The name of the mountain system derives from the ancient Roman region of Baetica, one of the Imperial Roman provinces of ancient Hispania.

The Baetic System is made up of multiple mountain ranges that reach from western Andalusia to the Region of Murcia, southern Castile-La Mancha and southern Land of Valencia. To the north, the Baetic Ranges are separated from the Meseta Central and the Sierra Morena by the basin of the Guadalquivir. The Iberian System rises north of the eastern part of the Prebaetic System, the northernmost part of the Baetic System. The mountain ranges that are part of this system are generally aligned \along a southwest-northeast direction.

The best-known range of the Baetic System is the Sierra Nevada, which contains the Mulhacén, the highest mountain in continental Spain and in the Iberian Peninsula. The Rock of Gibraltar is also considered part of the Baetic System, but not the Cabo de Gata area further east which includes rocks of volcanic origin.

The Baetic System as a geological feature belongs to a larger orogeny usually called the Gibraltar Arc, which represents the westernmost edge of the Alpine Orogeny. The geodynamic mechanisms responsible for its formation are so far relatively unknown.

Geologically the Rif mountains in Morocco and the Serra de Tramuntana in the island of Majorca are, respectively, Soutwestern and Northeastern extensions of the Baetic System. The Gibraltar Arc geological region follows the Moroccan coast from Oujda in the east to Tangier in the west, then crosses the Strait of Gibraltar and goes east again from Cádiz to Valencia and the Balearic Islands.

The Baetic System is home to a number of Mediterranean forests, woodlands, and scrub plant communities, including shrublands, oak woodlands, broadleaf forests, and coniferous forests, which vary with elevation, soils, and topography.

The Baetic System, together with the Rif Mountains of Morocco, which face the Baetic Ranges across the Alboran Sea, is one of the Mediterranean basin's ten biodiversity hotspots, known to ecologists as the Baetic-Rifan complex. The Baetic mountains are home to a rich assemblage of Mediterranean plants, including a number of relict species from the ancient laurel forests, which covered much of the Mediterranean basin millions of years ago when it was more humid.

The Baetic System is divided into the following sub-chains:

The Penibaetic System includes the highest point in the peninsula, the 3,478 m high Mulhacén in the Sierra Nevada; other ranges and features are:

The Subbaetic System occupies a central position within the Baetic System. Highest point 2,027 m (6,650 ft) high Peña de la Cruz in Sierra Arana.

The Prebaetic System is the northernmost feature of the whole Baetic System. Highest point 2,382 m high La Sagra.

• Geography of Spain
• Geology of the Iberian Peninsula
• Baetic Depression
• Tabernas Desert

• Sierra Nevada Natural Park
• Sierra del Aljibe
• Parque Natural de la Sierra de los Filabres y comarca del Alto Almanzora
• Cuenca del Guadalquivir