Insecure access to nutritious food is a common experience for poor households in developing countries. Despite the global scale of food insecurity, it has not been conceptualized by sociologists as a significant component of home environment or dimension of poverty that might matter for children's outcomes. Analyzing data from rural China, the authors show that nutritional environment in the home is associated with household socioeconomic status, that it predicts children's school performance, and that it is a significant mediator of poverty effects on schooling for children in early primary grades.