Food insecurity, a public health problem, is associated with worse academic and mental health outcomes in adolescents. Correlates of cognitive difficulty among adolescents include neurodevelopmental disorders, psychiatric conditions, and adverse childhood experiences (ACEs). We examined the association between parent-reported food insecurity and cognitive difficulties, after statistically adjusting for neurodevelopmental disorders, psychiatric conditions, and ACEs.The 2021 National Survey of Children’s Health is a parent-reported survey of youth in the United States that addresses their physical and emotional health. Associations between cognitive difficulty, food insecurity, neurodevelopmental and psychiatric conditions, and ACEs were examined using chi-squared tests and binary logistic regressions.Participants were 13,448 adolescents (aged 13–17; 48% girls), and 13.5% had parent-reported cognitive difficulties (14.7% of boys and 12.2% of girls). Among those with cognitive problems, 95% had a diagnosis of a neurodevelopmental or psychiatric condition. In the total sample, 21.7% were rated as having mild food insecurity and 3.4% had moderate–severe food insecurity. ACEs were associated with food insecurity and cognitive difficulties. Binary logistic regressions examined the associations between food insecurity and cognitive difficulties after statistically adjusting for sex, ACEs, and neurodevelopmental and psychiatric conditions [χ2(4) = 3941.339, p < 0.001; Nagelkerke R2 = 0.465]. Food insecurity was independently associated with cognitive difficulty (Odds Ratio = 1.28; 95% confidence interval = 1.15–1.42).Food insecurity was associated with serious cognitive difficulty among adolescents in the United States after adjusting for sex, neurodevelopmental or psychiatric conditions, and ACEs. It is important to better understand the correlates of cognitive difficulties among adolescents to bolster precision care designed to support youth with these difficulties.