Objective: This study examines the effectiveness of character strength-based cognitive (SCBC) and cognitive behavioral therapy (CBT) in improving college freshmen's mental health and positive traits. Methods: Freshmen were randomly assigned to SCBC, CBT or a PC group. Interventions included a 90-min session and a 7-day self-guided task. Assessments occurred at five time points: Preintervention (T1), postclass (T2), postintervention (T3), and at one-month (T4) and three-month (T5) follow-ups. Results: Both SCBC and CBT improved mental health. SCBC showed significantly greater self-efficacy gains at T4, while CBT demonstrated greater adjustability improvement at T2. Other differences were nonsignificant. Conclusion: SCBC and CBT positively impacted freshmen's mental health. The observed differences may stem from the distinct characteristics of SCBC and CBT. These findings can inform social workers in designing targeted mental health programs for college students.