The Hindu Kush (Persian: هندوکش, romanized: hindū-kuš, meaning Hindu-Killer) is an 800-kilometre-long (500 mi) mountain range in Central and South Asia to the west of the Himalayas. It stretches from central and western Afghanistan into northwestern Pakistan and far southeastern Tajikistan. The range forms the western section of the Hindu Kush Himalayan Region (HKH); to the north, near its northeastern end, the Hindu Kush buttresses the Pamir Mountains near the point where the borders of China, Pakistan and Afghanistan meet, after which it runs southwest through Pakistan and into Afghanistan near their border. The eastern end of the Hindu Kush in the north merges with the Karakoram Range. Towards its southern end, it connects with the White Mountains near the Kabul River. It divides the valley of the Amu Darya (the ancient Oxus) to the north from the Indus River valley to the south. The range has numerous high snow-capped peaks, with the highest point being Tirich Mir or Terichmir at 7,708 metres (25,289 ft) in the Chitral District of Khyber Pakhtunkhwa, Pakistan.

The Hindu Kush range region was a historically significant center of Buddhism, with sites such as the Bamiyan Buddhas. The range and communities settled in it hosted ancient monasteries, important trade networks and travelers between Central Asia and South Asia. While the vast majority of the region has been majority-Muslim for several centuries now, certain portions of the Hindu Kush only became Islamized relatively recently, such as Kafiristan, which retained ancient polytheistic beliefs until the 19th century when it was converted to Islam by the Durrani Empire and renamed Nuristan ("land of light"). The Hindu Kush range has also been the passageway for invasions of the Indian subcontinent, and continues to be important to contemporary warfare in Afghanistan.