Socioeconomic status affects a variety of mental and physical health outcomes, such as language development. Indeed, with poverty, disparities in the development of language processing are arguably among the most consistently found—with decreases in vocabulary, phonological awareness, and syntax at many different developmental stages. In this review, after considering basic brain systems affected by low socioeconomic status that are important for language development and related peripartum issues, we focus on two theoretical models that link poverty with the brain systems affected in language problems. The family stress model connects poverty with parental emotional distress that affects parenting, whereas the parental investment model involves a focus on basic needs that affects children’s language. Understanding the mechanisms through which poverty affects the brain, parenting behaviors and language development may have implications for identification and treatment of individuals as well as social policy.