The Carpathian Mountains or Carpathians () are a range of mountains forming an arc across Central Europe. Roughly 1,500 km (930 mi) long, it is the third-longest European mountain range after the Urals at 2,500 km (1,600 mi) and the Scandinavian Mountains at 1,700 km (1,100 mi). The range stretches from the far eastern Czech Republic (3%) and Austria (1%) in the northwest through Slovakia (21%), Poland (10%), Ukraine (10%), Romania (50%) to Serbia (5%) in the south. The highest range within the Carpathians is known as the Tatra mountains in Slovakia, where the highest peaks exceed 2,600 m (8,500 ft). The second-highest range is the Southern Carpathians in Romania, where the highest peaks range between 2,500 m (8,200 ft) and 2,550 m (8,370 ft).

The divisions of the Carpathians usually involve three major sections:

• Western Carpathians: Austria, Czech Republic, Poland and Slovakia
• Eastern Carpathians: southeastern Poland, eastern Slovakia, Ukraine, and Romania
• Southern Carpathians: Romania and eastern Serbia

The term Outer Carpathians is frequently used to describe the northern rim of the Western and Eastern Carpathians.

The Carpathians provide habitat for the largest European populations of brown bears, wolves, chamois, and lynxes, with the highest concentration in Romania, as well as over one-third of all European plant species. The mountains and their foothills also have many thermal and mineral waters, with Romania having one-third of the European total. Romania is likewise home to the second-largest area of virgin forests in Europe after Russia, totaling 250,000 hectares (65%), most of them in the Carpathians, with the Southern Carpathians constituting Europe's largest unfragmented forest area. Deforestation rates due to illegal logging in the Carpathians are high.