This study examined the relationship between lead exposure and attention regulation in children from low-income families. Children with lead exposure were expected to have lower attention regulation abilities than children who were not exposed. The 57 participants (39% male, 61% female) were children aged 4 and 5 years (mean age 4y 7mo [SD 5mo]); 24 children were lead-exposed (10-29microg/dl) and 33 were non-exposed comparisons (1-6microg/dl). Both groups qualified to be enrolled in programs for low-income families. A puzzle-matching task was completed in parent-child and child-alone conditions. Attention allocation and puzzle-matching performance were assessed in the two conditions. Children who were lead-exposed demonstrated less self-regulated attention than comparisons and had poorer puzzle performance in the child-alone condition. Attention patterns did not differ in the parent-child condition. This study extends previous knowledge concerning effects of lead exposure on preschool children from disadvantaged environments and suggests that lead exposure affects specific attention regulation abilities.