This paper examines the use of slang in the Uzbek and Turkish languages and analyzes its influence on cultural processes and language development. Slang is viewed as a dynamic and expressive layer of vocabulary that reflects social changes, youth culture, and contemporary modes of communication. The study explores the sociolinguistic functions of slang, its role in informal interaction, and its gradual penetration into the standard language through mass media, social networks, and popular culture. By comparing Uzbek and Turkish slang, the research identifies both shared tendencies shaped by globalization and language contact, as well as culture-specific features rooted in national traditions and social norms. The findings suggest that while slang enriches lexical diversity and communicative expressiveness, it also raises concerns regarding language norms and standardization. The paper contributes to contrastive linguistics and linguacultural studies by highlighting the interaction between slang, culture, and language evolution.