Background: Childhood cancer is a chronic life-threatening disease and requires a variety of therapies. The key to successful treatment is early detection and treatment adherence. Parental psychosocial and socioeconomics are factors that support a successful treatment. Objective: To determine the differences in the influence of maternal psychosocial and socioeconomics on adherence to cancer treatment in children. Method: A cohort study in pediatric patients with cancer and their mothers who were treated at Haji Adam Malik General Hospital, Medan in June 2019-April 2020. Maternal psychosocial assessment with the IES-R questionnaire after knew the diagnosis of cancer in her child and socioeconomic assessment through a questionnaire. Cancer treatment adherence was assessed for six months undergoing treatment. Bivariate analysis used the fisher's exact test to assess differences in the effect of each variable. Result: Of the 47 subjects observed, it was found 14.9% of children with cancer were not adherent the treatment. For the research data analyzed there was no significant difference between maternal psychosocial status, education and occupation of the mother, and residence ownership towards the adherence to cancer treatment in children. Total family income had a significant effect on adherence to cancer treatment in children (p = 0.042), even though all patients used the National Health Insurance (JKN). Conclusion: Total amount of family income used as an indicator of socioeconomic status has an influence on adherence of cancer treatment in children.