Research that has examined the association between specialization and injury in basketball has been limited to cross-sectional or retrospective studies. To determine whether specialization is a risk factor for injury among high school basketball athletes. Prospective cohort study. Basketball players from 12 high schools participating in the National Athletic Treatment, Injury, and Outcomes Network Surveillance Program (NATION-SP) were recruited prior to the 2022-2023 interscholastic basketball season. 130 athletes (mean age (SD) = 15.6 (1.3); girls' basketball: n=68 (52.3%)). Participants completed a questionnaire prior to the start of their school basketball season that had questions regarding participation in various specialized sport behaviors. During the basketball season, the school's athletic trainer reported all athletic exposures (AEs) and injuries (regardless of time loss) for participating athletes into NATION-SP. Injury incidence (IR) and incidence rate ratios (IRR) with 95% confidence intervals [95%CI] were calculated for the specialized sport behaviors previously described. There was no difference in injury risk between highly specialized and low specialized athletes (IRR [95%CI]: 1.9 [0.9, 3.7]). Players who participated in basketball year-round were twice as likely to sustain an injury compared to those who did not play year-round (IRR [95%CI]: 2.1 [1.1, 3.6]). Similarly, players who reported participating in basketball skills camps were at increased risk of injury compared to athletes who did not participate in basketball skill camps (IRR [95%CI]: 2.5 [1.2, 5.7]). Injury risk related to sport specialization in basketball may be specific to certain behaviors such as year-round play and participation in skills camps. Validated measures of comprehensive sport activity are needed to better measure specialization in youth sports to better determine injury risk related to sport specialization and develop injury prevention programs for basketball athletes.