Early childhood is considered to be a period of rapid development, with the acquisition of abilities predicting future positive school competences. Motor, cognitive and social difficulties related to cancer therapies heavily impact the development of children with cancer. This study focused on two main aims: to assess the developmental pathways of preschool children with acute lymphoblastic leukaemia one year post-treatment and to compare these abilities both with those of a control group of healthy peers and with Italian norms. Forty-four children and their families, recruited through the Haematology-Oncologic Clinic of the Department of Child and Woman Health (University of Padua), agreed to participate to this study. The children’s mean age was 4.52 years (SD = 0.94, range = 2.5-6 years), equally distributed by gender, all diagnosed with Acute Lymphoblastic Leukaemia. Matched healthy peers were recruited through paediatricians’ ambulatories. Each family was interviewed adopting the Vineland Adaptive Behaviour Scales. Paired sample Wilcoxon tests revealed that children were reported to have significantly more developmental difficulties than their healthy peers. When compared with Italian norms they scored particularly low in verbal competence, social and coping skills. No significant association were found between treatment variables and developmental abilities. These findings suggest that the creation of specialized interventions both for parents and children may fill the possible delays in children’s development probably due to stress, lack of adequate stimulation or difficult adaptation.