Khuan Kalong (Thai: ควนกาหลง, pronounced [kʰūa̯n kāː.lǒŋ]) is a district (amphoe) of Satun province, southern Thailand.

The minor district (king amphoe) Khuan Kalong was established on 1 June 1969 by splitting the three tambons Thung Nui, Pae-ra, and Tha Phae from Mueang Satun district.

In 1996 the northwestern part was split off to form Manang district Neighboring districts are (from the north clockwise) Palian of Trang province; Pa Bon of Phatthalung province; Rattaphum, Hat Yai, Khlong Hoi Khong and Sadao of Songkhla province; and Khuan Don, Tha Phae, La-ngu and Manang of Satun Province.

The district is divided into three sub-districts (tambons), which are further subdivided into 31 villages (muban).

There are no municipal (thesaban) areas, and three tambon administrative organizations (TAO).