Parents of children undergoing a bone marrow transplantation are considered to experience anxiety and depression during the acute phase of their children’s transplantation. Purpose: of this study was to explore factors associated with anxiety and depression in parents of children undergoing a bone marrow transplantation. Methods: The sample of the study consisted of 100 parents of children undergoing a bone marrow transplantation from public Children’s Hospital in Attica during the period of December 2020 – February 2021. Data were collected via interviews using the questionnaire "The Hospital Anxiety and Depression Scale (HADs). Results: Of 100 participants eighty-one and 64% of parents experienced anxiety and depression respectively, based on HADs scores. A statistically significant association was observed between parental anxiety and gender (p = 0.017), how often they visited the hospitalized child (p = 0.023), whether they would like other family members to also remain in the hospital (p = 0.033). Regarding depression, a statistically significant association was observed with difficulties encountered during the hospitalization (p = 0.034), whether they would like other family members to remain in the hospital (p = 0.009). Conclusion: Planning and application of psychological intervention protocols, before the admission to a pediatric bone marrow transplantation unit, can play a significant role in the reduction of anxiety and depression of parents of these patients and make their hospital stay easier.