Background: Sickle Cell Disease (SCD) is a genetic condition associated with painful vaso-occlusion episodes (VOE), chronic pain, and organ damage. Painful VOE and chronic pain can hinder daily activities and thus affect Quality of Life (QoL). The transition period of SCD patients from pediatric to adult care is often marked by frequent hospitalizations, complications and higher mortality. Our study evaluated patient reported health related QoL outcomes in SCD patients who transitioned from pediatric to adult care. Methods: This is a descriptive study of SCD patients receiving medical care at Newark Beth Israel Medical Center. The informed consent and assent were obtained from patients and/or legal guardians. Enrolled patients filled out a questionnaire using seven domains from the Adult Sickle Cell Quality of Life Measurement Information System (ASCQ-Me): pain episodes, medical history, pain impact, sleep impact, social functioning, stiffness, and emotional impacts. Eligible patients were aged 16-25 years, presenting to the pediatric or adult hematology clinic for their well visit. Recruitment took place from December 2021 to April 2023. Results: Seventy-six individuals were enrolled and questionnaire was administered. Most were aged 16-21 years with homozygous sickle cell disease. Pain episodes: 10-18% of 16-20 year-olds reported pain attacks in the previous year, while 43-100% of 21-25 year-olds reported pain attacks. Among 22-25 year-olds, 25-50% could not do most things that they usually did or relied on family or friends compared to 40-83% of 16-21 year-olds. Pain impact: 50-100% of 22-24 year-olds struggled all day due to pain, while most younger patients were unaffected. About 25-60% of 20-25 year-olds were occasionally, rarely, or never pain-free. In the sleep impact domain, 29-60% of 20-25 year-olds did not get enough sleep, and 20-60% of all ages stayed up most of the night due to difficulty falling asleep. Medical history: 17-36% of 16-20 year-olds and 40-100% of 21-25 year-olds used daily pain medicine. Sickle cell complications affected 8-40% of patients in all age groups. Social functioning domain: 25-60% of 20-25 year-olds often or always had their health that kept them away from doing something fun. Also, 16-17 year-olds (21%) and 20-22 year-olds (25-60%) reported that their family felt that they were a burden. No significant findings were noted in stiffness impact across all age ranges. Emotional impact: 25-83% of all patients were often or always sad about their health (70% of 16 year-olds and 83% of 21 year-olds). Nine % (19 year olds) to 83% (21 year olds) were depressed about their health problems and 21 year olds seemed most affected by emotional impact of their disease. Conclusion: Our cross-sectional study revealed a significant impact of SCD on HRQoL during the transition years from childhood to adulthood. Therefore, screening for mental health in patients aged 16-25 years is crucial, offering support to those at risk. Disease-modifying therapy adherence should be emphasized. Limitations of our study include a small sample size, especially in the older age group. Further studies may be needed to assess age and genotype stratified HRQoL outcomes for 16-25-year-old SCD patients and potential improvement measures.