Indigenous language usage in advertising remains a critical strategy for reaching diverse audiences in multilingual societies, yet systematic documentation of such practices in South-East Nigeria remains limited. This study conducted a comprehensive content analysis of indigenous language usage in radio jingles and advertisements broadcast across Enugu-based radio stations. Using a quantitative content analysis design, 384 radio jingles and advertisements were systematically sampled from five major radio stations (Radio Nigeria Enugu, Coal City FM, Urban Radio, Dream FM, and Owelle FM) over a six-month period from January to June 2025. Data were collected using structured coding sheets and analysed through frequency distribution, percentages, and chi-square testing. Anchored on Uses and Gratifications Theory, the findings revealed that only 31.5% of total advertisements employed indigenous language content, with 62.8% using code-switching between English and Igbo. Telecommunications (28.4%), consumer goods (24.1%), and health products (18.2%) dominated indigenous language advertising. Linguistic analysis showed extensive use of proverbs (45.3%), metaphors (38.7%), and cultural idioms (32.1%) to enhance persuasive appeal. Statistical testing (χ²=147.82, df=4, p<0.001) confirmed significant relationships between product categories and indigenous language usage intensity. The study recommends increased indigenous language content quotas, advertiser education programs on cultural communication benefits, development of standardized Igbo advertising lexicons, and policy frameworks incentivizing indigenous language commercial content to enhance cultural preservation and advertising effectiveness.