Using large-scale surveys from nine states, the Community Childhood Hunger Identification Project (CCHIP) estimates that 8% of American children under the age of 12 years experience hunger each year. CCHIP operationalizes child hunger as multiple experiences of parent-reported food insufficiency due to constrained resources. The current study examined the relationship between food insufficiency and school-age, low-income children's psychosocial functioning. The study also assessed the interinformant (parent versus child) reliability and time-to-time reliability of the CCHIP measure. Method: Two hundred four school-age children and their parents from four inner-city public schools were interviewed using parent, teacher, and clinician report measures of psychosocial functioning. Ninety-six children and their parents were reinterviewed 4 months later. Hungry and at-risk for hunger children were twice as likely as not-hungry children to be classified as having impaired functioning by parent and child report. Teachers reported higher levels of hyperactivity, absenteeism, and tardiness among hungry/at-risk children than not-hungry children. Parent and child reports of hunger were significantly related to each other, and time-to-time reliability of the CCHIP measure was acceptable. Results of this study suggest that intermittent experiences of food insufficiency and hunger as measured by CCHIP are associated with poor behavioral and academic functioning in low-income children. The current study also supports the validity and reliability of the CCHIP measure for assessing hunger in children.