This article explores the impact of age on second language acquisition, examining how cognitive development, learning strategies, and the critical period hypothesis influence language learning across different age groups. Young children, benefiting from high brain plasticity, often achieve near-native fluency and pronunciation through natural, immersive learning. Adolescents and adults, while struggling with pronunciation, leverage advanced cognitive skills and structured learning environments to grasp complex grammatical structures. The critical period hypothesis suggests a limited window for optimal language learning, typically ending around puberty. Practical implications for language education include immersive, play-based programs for children and structured, strategy-rich instruction for older learners, ensuring effective language acquisition across all ages.