This study aimed to evaluate the effectiveness of a short mindfulness intervention on anxiety, stress and depression symptoms, as well as on inhibition of dominant responses and academic performance among university students. Fifty volunteers (M(age) = 23.8; SD = 5.3) with high levels of depression, anxiety or stress were randomly allocated to a mindfulness practice group or an active control group (listening to stories). Students who underwent the mindfulness practice had decreased levels of anxiety, stress and depression compared to the control group. The mindfulness program also had a beneficial impact on the students’ academic performance. There was no change in the ability to inhibit dominant responses to neutral stimuli (letters); however, we observed a change in responses to neutral faces. Further research perspectives and the clinical implications of the study are discussed.