Objective To assess the clinical utility of the Distress Thermometer (DT) in children with hematological diseases via utilizing Smart′s multidimensional model of clinical utility (the focus of which included accessibility, appropriateness, practicability, and acceptability), so as to provide a valuable tool assessing psychological distress for this population.Methods A total of 125 children with hematological diseases were selected using convenience sampling method, then they were investigated by utilizing a general information questionnaire, the Chinese version DT, and the Children′s Depression Inventory (CDI).Results The effective response rate of the survey was 92.59%.The average scores of the children′s understanding and evaluation of the DT were above 2.3 points.Taking CDI as the gold standard, when the participants scored 3.5 points in DT, its sensitivity and specificity was 0.905 and 0.635, respectively.Conclusion The DT shows good clinical utility in children with hematological diseases, and it can serve as an effective assessment tool for psychological distress in this population.