Changes in word production occur across the lifespan. Previous studies have shown electrophysiological, temporal, and functional differences between children and adults accompanying behavioral changes in picture-naming tasks (Laganaro et al., 2015). Thus, a shift towards adult-like processes in referential word production occurs somewhere between the ages of 13 and 20. Our aim here was to investigate when and how the youngsters develop an adultlike behavior and brain activation in word production. To this aim, performance and eventrelated potentials (ERP) in a referential word production task were recorded and compared between two groups of adolescents (aged 14 to 16 and 17 to 18), children (aged 10 to 13) and young adults (aged 20 to 30). Both groups of adolescents displayed adult-like production latencies, which were longer for children only, while accuracy was lower in the younger group of adolescents and in children, compared to adults. ERP waveform analysis and topographic pattern analysis revealed significant inter-group differences in key time-windows on stimuluslocked ERPs, both early (150-220 ms) – associated with pre-linguistic processes, and late (280-330 ms) – associated with lexical processes. The results indicate that brain activation underlying referential word production is completely adult-like in 17 years-old adolescents, whereas an intermediate pattern is still observed in adolescents aged 14 to 16 years old, although their production speed, but not their accuracy, is already adult-like.