Turks have spread to many parts of the world throughout history. They established states in the regions where they migrated and made their culture recognized. One of the regions where the Turkish presence is known is Afghanistan. Afghanistan, which is strategically important, has hosted many nations. In the region, which has been under the influence of various civilizations, the Khalajs are an important ethnic group and have encountered different cultural, religious, and political interactions throughout history. In this study, the origins, and interactions of the Khalajs in the pre-Islamic period have been analyzed through travelogues and epics accompanied by historical and archaeological sources. In the sources on the Khalajs, we see that they are mentioned in the forms of Khalaj, Kalach Hılci, and Halluh in relation to their names. Especially there are studies on the connection of the name Halluh with Karluks. However, mistakes have been made due to the spelling of the sources. It is seen that the Khalajs also existed in the period when the Turks continued their existence in the 5th–7th centuries. In our study, it is also aimed at conveying this issue with archaeological data. Considering the geographies and linguistic differences of the Khalajs, the Akhun/Eftalit-Khalaj connection and their ethnic origins are emphasized. The aim of this study is to examine the interactions of the Khalaj with other ethnic groups in the pre-Islamic period and their effects on cultural changes. It aims to understand the structure of Afghanistan`s geography and the historical and cultural heritage of the Khalaj.