The Aśvakas or Aśvakayanas, classically called the Assacenii/Assacani (Sanskrit: अश्वक), is the Sanskrit name of a people who supposedly lived in northeastern Afghanistan and the Peshawar Valley. They are/were believed to be a sub-group of the Greater Kamboja tribe profusely referenced in ancient Sanskrit/Pali literature and were partitioned into eastern and western Aśvakas. They find mention in the Puranas, Mahabharata and numerous other ancient Sanskrit and Pali texts. Today, their descendants are mostly heterogeneous people.

The Sanskrit term aśva, Iranian aspa and Prakrit assa means horse. The name Aśvaka/Aśvakan or Assaka is said to be derived from Sanskrit Aśva or Prakrit Assa and it literally denotes someone connected with the horses---hence: a horseman, or a cavalryman or "breeder of horses". The Aśvakas were especially engaged in the occupation of breeding, raising and training war horses, as also in providing expert cavalry services to outside nations, hence they also constituted an excellent class of Kshatriyas (warriors). Like tribal term Kamboja, the tribal term Aśvaka is also interpreted as land or home of horses.