Sagittal spinopelvic configuration and global alignment have previously been investi-gated in healthy children, adolescents, and adults to understand biomechanics or to guide fusion surgery. However, no studies were found in the literature assessing patients with structural hyperkyphosis (HK) from the perspective of global alignment and spinopelvic parameters. The research question is: How does structural HK affect spinopelvic parameters, global tilt(GT), global alignment, and proportion (GAP) score in skeletally immature adolescents? This was a retrospective analysis of prospectively col-lected data. Thirty-two structural HK patients(19 male, 13 female) with a mean age of 13.8 years and an initial curve magnitude between 55-75° were included in the study. Radiographic measurements including thoracic kyphosis(TK) angle, L1-S1 lumbar lordo-sis(LL) and L4-S1 lower arch lordosis angles, pelvic incidence, sacral slope, global tilt were measured from lateral spine radiographs by a blinded orthopedic spine surgeon at the first visit, and GAP score was calculated using these parameters. The mean TK was 59.5°, LL was 66.7°, and the mean GT was 7.2° at baseline. There was a correlation be-tween TK and LL, meaning that patients who have higher TK have also a higher degree of LL. There was also a correlation between PT and SS with the PI at baseline. Structural HK may affect pelvic development resulting in lower values of PI. Higher values of TK or thoracolumbar kyphosis may be sufficiently compensated by LL to maintain a neutral sagittal balance when PI has lower values. Clinicians should focus on global alignment to maintain the global sagittal balance rather than TK alone. Keywords: Scheuermann's disease, hyperkyphosis, global alignment, sagittal balance, spinopelvic configuration