Given the high prevalence of emotional disorders among college students, its high social, emotional and economic costs, and a large treatment gap, we designed and evaluated a preventive group intervention based on the Unified Protocol for the transdiagnostic treatment of emotional disorders (UP; Barlow et al., 2011). A total sample of 128 college students in a state university in Bogotá (Colombia) was recruited for this quasi-experimental study with three assessment points: pre-treatment, post-treatment, and three-month follow-up. Participants were included in the control or intervention conditions based on non-random assignement. At the end of the intervention, group analysis suggested significant declines in transdiagnostic risk factors and neurotic temperament and gains in mindfulness, perceived control, and emotional dysregulation. Significant declines were found also for emotional variables such as stress, anxiety, and depression. These results suggest that a preventive intervention based on the Unified Protocol may have a significant impact on several transdiagnostic risk factors and emotional variables making it a promising prevention and mental health promotion program for college students. Since this is the first Colombian study on the matter, its replication and the use of larger and more diverse samples are recommended for future research.