Sariska Tiger Reserve is a tiger reserve in Alwar district, Rajasthan, India. It stretches over an core tiger habitat area of 881 km (340 sq mi) and 322.23 km² of buffer area making 1203.34 km² total area of tiger reserve. It is comprising scrub-thorn arid forests, dry deciduous forests, grasslands, and rocky hills. This area was preserved for hunting, for the Alwar state and was declared a wildlife sanctuary in 1958. It was given the status of a tiger reserve making it a part of India's Project Tiger in 1978. The wildlife sanctuary was declared a national park in 1982, with a total area of about 273.8 km (105.7 sq mi). It is the first reserve in the world with successfully relocated tigers. It is an important biodiversity area in the Northern Aravalli leopard and wildlife corridor.
The park is a part of the Aravalli Range and the Khathiar-Gir dry deciduous forests ecoregion. It is rich in mineral resources, such as copper. In spite of the Supreme Court's 1991 ban on mining in the area, marble mining continues to threaten the environment.