The link between childhood maltreatment and mood disorders is complex and involves multiple bio-psycho-social factorsthat affect multiple molecular pathways. The present narrative review aims to clarify the current understanding of the impact ofchildhood maltreatment on biomarkers in patients with mood disorders and their first-degree relatives. Neurotransmitters, such asserotonin, dopamine, norepinephrine, and hormones (eg the stress hormone cortisol), play a crucial role in regulating mood andemotion. Childhood maltreatment can alter and affect the levels and functioning of these neurotransmitters in the brain; further,childhood maltreatment can lead to structural and connectivity changes in the brain, hence contributing to the development of mooddisorders and moderating illness presentation and modifying response to treatments. Childhood maltreatment information, therefore,appears mandatory in treatment planning and is a critical factor in therapeutic algorithms. Further research is needed to fullyunderstand these pathways and develop new treatment modalities for individuals with mood disorders who have experiencedchildhood maltreatment and effective preventive interventions for individuals at risk of developing mood disorders.