The Sierra de Grazalema Natural Park is a natural park in the northeastern part of the province of Cádiz in southern Spain. The park encompasses, within its 51,695 hectares, a complex of mountain ranges, known collectively as the Sierra de Grazalema, which, in turn, are part of the Cordillera Subbética. Other ranges within the park, comprising the Sierra de Grazalema, include the Sierra de Zafalgar, the Sierra del Pinar, and the Sierra de Endrinal. Pinar, 1654 metres in elevation, is the tallest peak.
The Sierra de Grazalema, a karstic region, contains a number of large limestone caverns, including the Cueva del Gato, the Cueva de la Pileta and the Garganta Verde.
The Sierra de Grazalema is also home to many colonies of vultures, including a few pairs of Egyptian vultures, a species which is seriously threatened. The natural park was declared a biosphere reserve in 1977.