Qasr may refer to:
- the Arabic for "castle" (from Latin castrum), see Ksar
- Qasr Libya - a town in Libya
- Qasr Ahmed - the port for the Libyan city of Misurata
- Qasr Amra - a desert castle in Jordan
- Qasr Azraq - a desert castle in Jordan
- Qasr Ibrim - an archeological site in Lower Nubia
- Qasr Kharana - a desert castle in Jordan
- Qasr al Abd - a large ruin in western Jordan
- Qasr al-Hosn - the oldest stone building Abu Dhabi, United Arab Emirates
- Qasr alheer algharbi - a castle in Syria
- Qasr alheer alsharqi - a castle in Syria
- Qasr ibn Wardan - a castle in Syria
- Qasr, Fariman - a village in Fariman County, Razavi Khorasan Province, Iran
- Qasr, Mashhad - a village in Mashhad County, Razavi Khorasan Province, Iran
- Qasr prison - a prison in Tehran, Iran
- Qasr-e-Shirin County - a county in Kermanshah Province, Iran
- Sayyidat al-Qasr - a 1958 Egyptian romance film
- Umm Qasr - a city in Iraq
- Battle of Umm Qasr - the first military confrontation in the Iraq War