Purpose: The purpose of this study was to evaluate whether preschoolers with primary language impairment (PLI) show deficits in executive function (EF) compared with their peers with typical development (TD) when inhibition, updating, and mental-set shifting are examined using both linguistically based and visually based tasks. Method: Twenty-two 4- and 5-year-old preschoolers with PLI and 30 preschoolers with TD completed 2 sets of computerized EF tasks: 3 that were linguistically based and 3 that were visually based. This permitted us to test the hypothesis that poor performance on EF tasks in preschoolers with PLI results from impaired language rather than impaired EF. Results: The PLI group scored significantly lower than the TD group on linguistically and visually based updating tasks and mental-set shifting tasks. The PLI and TD groups did not differ significantly for accuracy or response time on linguistically and visually based inhibition tasks. Conclusion: Results suggest that preschool-age children with PLI have domain-general EF deficits in updating and mental-set shifting but not inhibition deficits, as measured by our tasks.