The city of Kerman has been hosting a significant population of Afghan immigrants for decades. Two population groups live side by side in this city: the majority of native Iranians and the minority of Afghan immigrants, who are themselves divided into several generations. Our issue in this article is to examine the process of linguistic identity assimilation of the third generation of Afghan immigrants (those who were born in Iran and their parents) in the city of Kerman. To conduct the research, the ethnographic method and in-depth interview techniques with 40 people, extensive participatory observation, and content analysis were used. The third generation of Afghan immigrants experience a special situation due to their common cultural characteristics (birth and full socialization in Iran, deep generational disconnection from Afghanistan, monolingual Persian with a Kermani dialect). This situation, which is an extension of Turner's concept of liminality to "permanent generational liminality," can be explained as the result of a process of complete assimilation and long-term acculturation. The results of this study indicate that third-generation linguistic assimilation, influenced by factors such as the symbolic capital of the host dialect, systematic linguistic discrimination, long-term educational immersion, persistent fear of rejection and repatriation, and a deep generational disconnect, has shifted from an integration strategy to full assimilation, leading to Persian monolingualism, a break from the mother tongue, and the formation of a hybrid identity.