The endocannabinoid system exerts a crucial neuromodulatory role in many brain areas that is essential for proper regulation of neuronal activity. The role of cannabinoid signalling controlling neuronal activity in the adult brain is also evident when considering its contribution to adult brain insults or neurodegenerative diseases. In the context of brain genetic or acquired encephalopathies administration of cannabinoid-based molecules has demonstrated to exert symptomatic relief and hence, they are proposed as new potential therapeutic compounds. This review article summarizes the main evidences indicating the beneficial action of cannabinoid-derived molecules in preclinical models of neonatal hypoxia/ischemic damage. In a second part, we discuss the available evidences of therapeutic actions of cannabidiol in children with refractory epilepsy syndromes. Finally, we discuss the current view of cannabinoid signalling mechanisms active in the immature brain that affect in neural cell fate and can contribute to long-term neural cell plasticity.