Abstract Introduction: Retinoblastoma is the most common ocular malignancy of childhood. At the onset of retinoblastoma diagnosis, parents must learn about retinoblastoma and its complex management, while managing concerns around their child's health and wellbeing. Coping methods are action-oriented efforts to manage, master, tolerate, reduce or minimize the demands of a stressful environment, such as a cancer diagnosis in the family. The purpose of this study was to assess parental coping to the diagnosis of retinoblastoma in their child. The study also aimed to identify factors that assist and/or detract from parental ability to cope. Methodology: Eligible study participants included parents or guardians of children diagnosed with retinoblastoma who were present during the child's retinoblastoma diagnosis and treatment. Study participants completed a print (China, Mandarin language) or online (North America, English language) questionnaire that collected: 1) basic demographic information and information pertaining to the child's retinoblastoma diagnosis; 2) responses to the Mini Mental Adjustment to Cancer Scale (Mini-MAC), a validated scale that assesses coping by measuring levels of helplessness/hopelessness, anxious preoccupation, fighting spirit, avoidance and fatalism; 3) responses to the Hospital Anxiety and Depression Scale (HADS), a validated scale that determines the levels of anxiety and depression experienced by the participant; and 4) additional information on health literacy, self-determination and social support. Coping strategies assessed by the Mini-MAC that correlated with low HADS scores were deemed adaptive (i.e. factors that aided in coping), while methods that correlated with high HADS scores were maladaptive (i.e. factors that detracted from coping). All models were analyzed with multivariate linear regression and significance was set at p<0.05. Results: A total of 153 retinoblastoma parents participated in the study; 30.7% (47/153) were from North America and 69.3% (106/153) were from China. Chinese parents tended to have a lower correlation with anxiety and depression (R = 0.51) than North American parents (R = 0.71). For the North American cohort, high scores for helplessness/hopelessness and anxious preoccupation appeared to be maladaptive, as they correlated with increased anxiety and depression. In contrast, the Chinese cohort demonstrated that feelings of helplessness/hopelessness and anxious preoccupation were adaptive, as they correlated with reduced anxiety and depression. For the Chinese cohort, anxious preoccupation was also positively correlated higher parental health literacy. Conclusions: We observed significant differences in coping between North American and Chinese parents of children with retinoblastoma, which may be explained by cultural differences. The results of this study may help healthcare teams better care for the psychosocial needs of families affected by retinoblastoma. Citation Format: Trillium E. Chang, Yan Zhang, Chengyue Zhang, Junyang Zhao, Khairi Yi, Helen Dimaras. Parental coping to retinoblastoma at the onset of diagnosis: A global study. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 3479.