AIM: To determine the temporal retinal vessel angle in babies and its relation to preterm birth. METHODS: Digital images were obtained during routine screening for retinopathy of prematurity (ROP). The temporal retinal vessel angle was measured in 164 eyes of 82 babies born "very preterm" (24-27 weeks gestational age (GA)), "preterm" (28-31 weeks GA), and "near term" (>/=32 weeks GA). RESULTS: Mean temporal vessel angle (TVA) for all three GA groups together is 80.0 degrees (SD 17.0 degrees ) for the right eye and 80.5 degrees (16.7 degrees ) for the left eye. The range is right eye 59-106 degrees , left eye 69-97 degrees , with 95% data above 67 degrees for the right and 63 degrees for the left eye. For babies born near term, TVA is 82 degrees in each eye. There is a high degree of interocular symmetry between right and left eyes and a statistically insignificant trend for increasing TVA with increasing GA. The presence and stage of ROP affected one parameter of the left eye alone. CONCLUSIONS: These data provide normative data on the TVA in babies and will facilitate, especially if there is interocular asymmetry, determining whether there is macular displacement.