Purpose: This study investigated attentional shifting in preschool children with specific language impairment (SLI) compared to their typically developing peers. Children's attentional shifting capacity was assessed by varying attentional demands. Method: Twenty-five preschool children with SLI and 25 age-matched, typically developing controls participated. A behavioral task measuring attentional shifting within and across multiple dimensions (auditory, linguistic, and visual) was employed. Demands on attentional shifting were increased based on input dimension (low load: staying within dimension; medium load: shifting between 2 dimensions; and high load: shifting among 3 dimensions). Results: Compared to controls, the group with SLI made more erroneous responses and exhibited longer response times. Although both groups' error rates were similarly affected by shifting compared to nonshifting trials, their response speed was not. The group with SLI exhibited a larger comparative decrement to their response speed in the high-- attentional load condition. Discussion: When demands on attentional shifting increase, children with SLI struggle to shift their attention as efficiently to changing stimuli as their unimpaired peers. Potential implications for the assessment and treatment of this population are discussed.