Problematic smartphone use (PSU) has become a prevalent issue worldwide. Previous studies suggest that physical exercising may effectively reduce smartphone users' addiction levels. Comparisons and further evaluations on the long-term effects of different types of exercise-based interventions on treating PSU remain to be investigated. Objective. We investigated if group-based basketball and Baduanjin exercise (a type of Qigong) would reduce PSU and improve the mental health of college students and whether such effects would be sustained. A twelve-week experiment was conducted, where 96 eligible Chinese college students with PSU were randomly assigned to two intervention arms (i.e., basketball and Baduanjin exercises) and a control arm. Outcome measures, including PSU (measured by the Mobile Phone Addiction Index in Chinese (MPAI)) and mental health indices for anxiety (measured by Self-Rating Anxiety Scale (SRAS)), loneliness (measured by the short-form of the UCLA Loneliness Scale (UCLA-LS)), inadequacy (measured by the revised Janis and Field's Feelings of Inadequacy Scale (FIS)), and stress (measured by the Chinese version of Perceived Stress Scale (CPSS)) were collected at the baseline, the end of week 12, and the two-month follow-up. A Generalized Estimating Equations (GEE) model for longitudinal data was utilized in analyses. Results. Both exercise interventions demonstrated significant effects on decreasing PSU (basketball: p<0.01; Baduanjin: p<0.01), feelings of anxiety (basketball: p<0.01; Baduanjin: p=0.04), loneliness (basketball: p<0.01; Baduanjin: p<0.01), inadequacy (basketball: p<0.01; Baduanjin: p<0.01), and perceived stress (basketball: p<0.01; Baduanjin: p=0.04), at the end of interventions. At two months after interventions, both exercise interventions demonstrated significant effects on decreasing PSU (basketball: p<0.05; Baduanjin: p<0.05), feelings of anxiety (basketball: p<0.01; Baduanjin: p=0.03), loneliness (basketball: p<0.01; Baduanjin: p<0.01), and inadequacy (basketball: p<0.01; Baduanjin: p=0.01), but not for feeling of stress. Furthermore, group-based basketball demonstrated larger improvements for all these significant results on reducing PSU and meanwhile improving their related mental health parameters among college students.