Infantile hemangiomas (IH) are common tumors for which there is no validated disease-specific instrument to measure the quality of life in infants and their parents/caregivers during the critical first months of life. This study prospectively developed and validated a quality-of-life instrument for patients with IH and their parents/caregivers and correlated demographic and clinical features to the effects on the quality of life. A total of 220 parents/caregivers completed the 35-item Infantile Hemangioma Quality-of-Life (IH-QoL) instrument and provided demographic information. The dimensionality of the items was evaluated using factor analysis, with results suggesting four factors: child physical symptoms, child social interactions, parent emotional functioning, and parent psychosocial functioning. Each factor fit the Rasch measurement model with acceptable fit index (mean square <1.4) and demonstrated excellent internal consistency, with alpha ranging from 0.76 to 0.88. The final instrument consists of four scales with a total of 29 items. Content validity was verified by analyzing parents' responses to an open-ended question. Test-retest reliability at a 48-hour interval was supported by a total IH-QoL intraclass correlation coefficient of 0.84. Certain clinical characteristics of hemangioma, including those located on the head and neck, in the proliferative stage, and requiring treatment, are associated with a greater impact on QoL.