This study investigated the longitudinal trajectories of peer rejection and their predictive effects on Internet gaming addiction among Chinese children. The sample comprised 818 students from Grades 1 to 3 (M = 8.30, SD = 1.11, 51.3% boys). Peer rejection was assessed using peer nominations in five waves over a period of 2.5 years, and Internet gaming addiction was measured using the Internet Gaming Disorder Scale--Short Form in the fifth wave. We used a growth mixture model to explore the developmental trajectory of peer rejection and identified four heterogeneous developmental trajectories: low-drop, moderate-drop, moderate-rise, and high-rise rejection. The trajectory categories of peer rejection significantly predicted Internet gaming addiction. In particular, the prediction in the moderate-rise rejection group was higher than that in the low-drop rejection group. This study indicates that exploring the prediction of trajectory categories on Internet gaming addiction is necessary and that it is essential for families and schools to help children establish good interpersonal relationships and to reduce the development of addictive behaviors associated with Internet gaming.