To evaluate choroidal changes over time in school-age children with a history of prematurity. A study of 416 eyes of 208 eligible participants, including 88, 190, 36, 56, and 46 eyes in the full-term control, preterm, spontaneously regressed retinopathy of prematurity, intravitreal bevacizumab (injection of bevacizumab)-treated retinopathy of prematurity, and laser-treated retinopathy of prematurity groups, respectively, were enrolled in this study. The choroidal thickness was measured 4 times at 6-month intervals using optical coherence tomography. Of all the groups, the laser-treated children had the thinnest choroid compared with full-term children (-52.3 µ m, P = 0.04). Preterm children exhibited greater attenuation in choroidal thickness over time than did full-term children (-6.3 ± 26.9 and -1.1 ± 12.8 µ m/year, P = 0.03), whereas no difference was observed between injection of bevacizumab and laser treatments (-4.6 ± 18.9 and -2.0 ± 15.7 µ m/year, P = 0.46). In all groups, the changes in axial length were negatively associated with the changes in choroidal thickness (all P < 0.05). A greater attenuation in choroid thickness over time was observed in preterm children than in full-term children, but this attenuation did not differ between injection of bevacizumab and laser treatments. Axial elongation was associated with choroidal thinning in school-age children.