Background: There are no any clear evidence to date has evaluating patients and caregiver preferences for r-hGH (recombinant-human growth hormone) injection in children in Japan. This study quantitatively evaluated the factors driving preferences for daily r-hGH injection among Japanese children with Growth Hormone Deficiency (GHD) or their respective caregivers to determine the relative importance of treatment delivery attributes. This study was performed amongst Japanese children with GHD or their caregivers who visited a specialized clinic in Japan as part of their routine care between June and July 2020. Methods: The participants were asked to complete a web-based discrete choice experiment (DCE) questionnaire using a handheld tablet device during a routine clinical visit. DCE is a quantitative method widely used in healthcare to elicit preferences from participants in the absence of revealed preference data. Choice-based conjoint analysis was used to evaluate the relative importance of attributes as choice predictors and determine utilities for each attribute. Of the 47 respondents who participated in this study, 41 were caregivers who responded on behalf of the patients, and the remaining 6 were patients who completed the DCE themselves. All participants were screened by a clinician to ensure they met all eligibility criteria. Results: The injection schedule was found to be the most important attribute for both patients and caregivers (Relative importance: 43.6%); a once-weekly injection schedule was preferred over a daily injection schedule. For maintenance of injection devices, patients had a stronger preference for reusable pens which can be used by replacing cartridges, while caregivers preferred disposable pen devices. The storage and preparation attribute was deemed more important to patients than it was to caregivers, with patients preferring storage in room temperature even if it needed an additional mixing(reconstitution) step. Both patients and caregivers showed a clear preference for devices that offered a dose setting memory. Conclusion: The results of this study showed that patients prefer a once-weekly injection schedule over a daily injection schedule. A less frequent injection schedule should enhance adherence and compliance to r-hGH treatment over the long term and will also improve QoL in children with GHD. The benefits of a less frequent injection schedule can be further explored using real-world studies.