COVID-19 negatively impacts students' learning as well as physical and mental health. This study examined the effects of perceived online learning difficulties and cyberbullying on academic engagement and mental health, and if parenting styles and student-teacher relationship moderated these relations among 733 middle school students (54.3% boys) and their parents (M[subscript age] = 44.76 years, SD = 4.13 years, 28.1% fathers and 71.9% mothers) from Beijing, China. Results suggested that perceived online learning difficulties and cyberbullying predicted more mental health difficulties; perceived difficulties with online learning negatively predicted academic engagement. Authoritative parenting and positive student-teacher relationship predicted more academic engagement and less mental health difficulties, while authoritarian parenting predicted more mental health difficulties. Student-teacher relationship also moderated the relation between cyberbullying and mental health as well as difficulties with online learning and academic engagement. Parents and adolescents wanted more interactions with teachers and group activities to foster peer relationships, and more support from teachers and school psychologists to address students' social and emotional needs during COVID-19. Implications for school psychologists and school staff are discussed.