Maternal vitamin D deficiency affects brain development during foetal life and causes alterations that may persist into adulthood. A large number of observational studies have highlighted the prevalence rates of vitamin D insufficiency and deficiency in many populations including pregnant women. Vitamin D is well known to have a crucial role in differentiation and proliferation, as well as neurotrophic and neuroprotective actions in the brain. It has been observed that this micronutrient can modulate neurotransmission and synaptic plasticity. Recent results from animal and epidemiological studies indicated that maternal vitamin D deficiency is associated with a wide range of neurobiological diseases including autism, schizophrenia, depression, multiple sclerosis and developmental defects. The aim of this review is to summarize the current state of knowledge on the effect of maternal vitamin D deficiency on brain functions and development.