Background: Sickle cell disease (SCD) is the most common inherited hemoglobinopathy characterized by chronic hemolytic anemia, vaso-occlusive crises (VOCs), sensitivity to bacterial infections and multi-organ failure. Painful VOCs may severely impair the life of children with SCD and their families, resulting in limited health-related quality of life (HRQoL). Currently, there is limited information how HRQoL changes over time following hospitalization for VOC. Therefore, the aim of this study is to evaluate the longitudinal impact of hospital admission for VOCs on the HRQOL in children with SCD. Methods: In this retrospective cohort study, children between the age of 8 and 18 years with SCD treated at the Amsterdam University Medical Centers were included. As part of standard care, once a year, these children completed patient reported outcomes measures (PROMs) on the KLIK PROM portal (www.hetklikt.nu). HRQoL was measured with the Pediatric Quality of Life Inventory (PedsQL). The score is ranging from 0-100, and a higher score indicates better QoL. Data were analysed from the medical files of patients, who filled out at least two PedsQL questionnaires between 2012 and 2021. The effect of the occurrence and frequency of hospital admissions for VOCs on the HRQoL was evaluated 3, 6, 9 and 12 months following hospital admission, using a linear mixed model adjusted for age and SCD genotype. Results: In total, 94 children were included with a median age of 11.8 years (interquartile range: 9.3 - 14.1), including 57 patients (61%) with the severe genotype: HbSS or HbSβ0 thalassemia. During follow-up, 37 patients (41%) had been admitted to the hospital for a VOC. Hospitalization for VOC in the last 12 months led to a decrease of 3.2 points (p=0.053) in HRQoL as compared to patients without hospitalization. Recurrent admissions for VOC in the previous 12 months further decreased HRQoL with 2.3 points for every additional admission (p=0.035). The significantly affected domains were physical functioning at 6, 9 and 12 months, and school performance 12 months after hospitalization. Conclusion: Hospitalization for VOC in children with SCD is associated with a decreased HRQoL persisting up to 12 months after admission. These findings highlight the importance of using patient-reported outcomes in children with SCD to screen for the need for extra support after hospitalization for VOCs to optimize HRQoL.