General Sir John Kotelawala Defence University (KDU) (Sinhala: ජෙනරාල් සර් ජෝන් කොතලාවල ආරක්ෂක විශ්ව විද්යාලය General Sir John Kotelawala Arakshaka Vishva Vidyalaya) located at Kandawala, Ratmalana, Colombo, is a joint services academy where cadets of the three wings Sri Lanka Army, Sri Lanka Navy and Sri Lanka Air Force are trained before they go for their pre-commission training to their academies. Established in 1980 as the General Sir John Kotelawala Defence Academy, named after General Sir John Kotelawala, 3rd Prime Minister of Ceylon; it was elevated to the status of a university by an amendment bill passed in Parliament on 11 October 2007. In 2018, parliament of Sri Lanka passed the General Sir John Kotelawala Defence University (Special Provisions) Act to abolish medical faculty of South Asian Institute of Technology and Medicine and to transfer the students to General Sir John Kotelawala Defence University. General Sir John Kotelawala Defence University member of the Association of Commonwealth Universities.

Caledonian had supplied fire resistant and flame retardant power cables with earth wire for KDU which were popular items in internatioanal projects.