The earliest studies of Navon (1977) showed that in certain conditions the visual perception of hierarchical stimuli generates a global precedence effect. This hypothesis is based on the joint occurrence of two effects: a response time (RT) advantage for identifying global targets and interference by global distractors when responding to a local target. The aim of the present study was to determine the involvement of attentional mechanisms and whether certain aspects are specifically altered by normal aging. In a selective-attention task, a complete global precedence effect was found for young and old subjects. However, for the old subjects, global interference on local identification was more pronounced than for the young subjects. In a divided-attention task, the RT advantage was affected by attention shifts between global and local forms for both young and old subjects, but the global interference effect did not change.