Objective: To determine the association between exposure to entertainment screen content on mobile phones and symptoms of anxiety-depression co-morbidity among college students,so as to provide evidence for mental health interventions. Methods: A baseline survey was conducted from April to May 2019. A total of 1 135 college students were selected from one university each in Shangrao City, Jiangxi Province and Hefei City, Anhui Province using cluster random sampling method. A follow up study was conducted in November 2019, resulting in 1 110 matched valid responses. Self rating questionnaires were used to assess the exposure of entertainment screen content. The Depression Anxiety Stress Scale-21(DASS-21) and the Patient Health Questionnaire-9 (PHQ-9) were used to evaluate the anxiety symptoms, depressive symptoms, and symptoms of anxiety-depression co-morbidity among college students. A multivariate binary Logistic regression model was constructed following initial intergroup comparisons with Chi-square test to determine the association between baseline exposure to mobile entertainment screen content and the risk of symptoms of anxiety depression co-morbidity at baseline and the 6 month follow up. Results: The prevalence rates of symptoms of anxiety-depression co-morbidity among college students were 25.4% and 20.6% at baseline and follow up, respectively.After adjusting for confounding factors such as gender, self rated family economic status and self rated health status, the results of multivariate binary Logistic regression analysis showed that compared with the appropriate exposure level group, the exposure of entertainment screen content on mobile phones at baseline, including frequent exposure to reading( OR =1.65,95% CI =1.14-2.39), occasional exposure to other entertainment screen content ( OR =1.46,95% CI =1.01-2.10)and frequent exposure to other entertainment screen content( OR =1.76,95% CI =1.20-2.60), increased the co-occurrence risk of symptoms of anxiety-depression co-morbidity among college students during the follow up period (all P <0.05). Conclusion Occasional or frequert exposure to mobile entertainment screen content can increase the risk of symptoms of anxiety depression co-morbidity among college students.