Objective: To explore the trajectory of mobile phone addiction score and to investigate the relationship between subgroups of trajectory and anxiety with depression in college students, and to provide evidence for risk factors of anxiety and depression and mobile phone addiction prevention college students. Methods: A total of 1 562 college students were recruited from 2017 in Shandong University were followed longitudinally for five times by means of stratified cluster sampling. Mobile Phone Addiction Tendency Scale, Self-rating Anxiety Scale, and Self-rating Depression Scale were used, and latent class linear mixed models were used to identify the trajectory of mobile phone addiction score and Logistic regression models were used to explore the relationship between subgroups of trajectory with anxiety and depression. Results: At the last survey, the mean mobile phone addiction score was (42.9±5.4) and the prevalence of anxiety and depression was 33.7% (n=526) and 40.2% (n=628), respectively. The trajectories of mobile phone addiction score were classified into five groups: stable, high level-decreasing group, low level-rapid increasing group, moderate level-increasing group, and high level-increasing group. The number and proportion of the five groups were 701(44.9%), 309(19.8%), 96(6.2%), 232(14.9%), 224(14.3%), respectively. Compared with students of stable group, students in the moderate level-increasing and high level-increasing groups had higher risk of anxiety (OR=3.19, 95%CI=2.32-4.40; OR=8.38, 95%CI=5.09-13.77) and depression (OR=3.29, 95%CI=2.40-4.52; OR=4.49, 95%CI=2.82-7.16). Conclusion Mental health education in universities should start with mobile phone intervention, especially those with severe increasing tendency of mobile phone addiction, which would subsequently decrease the prevalence of anxiety and depression in college students.