A significant percentage of children suffer from neurodevelopmental aberrations, which have long-term effects on both individuals and society. Since the developmental timelines of different brain regions vary, the type, severity and timing of harmful exposures are crucial for understanding the specific pathological processes and consequences involved. During development, the cerebellum is one of the first brain structures to begin to differentiate, but one of the last to achieve maturity. This relatively long period underscores its vulnerability to detrimental environmental exposures throughout gestation. Moreover, as the postnatal functionality of the cerebellum is multifaceted, enveloping sensorimotor, cognitive, and emotional domains, prenatal disruptions in cerebellar development can result in a variety of neurological and mental health disorders. Here, we review major intrauterine insults that affect cerebellar development in both humans and rodents, ranging from abuse of toxic chemical agents such as alcohol and nicotine, to stress and sleep, malnutrition as well as infections. Understanding these pathological mechanisms in the context of the different stages of cerebellar development in humans and rodents may help us to identify critical and vulnerable periods and thereby to prevent the risk of associated prenatal and early postnatal damage that can lead to lifelong neurological and cognitive disabilities.