Stress is a major problem among university students due to the circumstances from internal as well as external such as relationship problems, low self-confidence, and academic pressure. We administered self-report questionnaires and acquired peripheral physiological signals to observe the effectiveness of a brief mindfulness-based intervention (MI) in improving relaxation and thus reducing stress. It was found that skin conductance (SC) showed significant change with p=0.0016 after MI unlike blood volume pulse (BVP) and respiratory rate (RR), even though both were found to be slightly better than that before MI during the resting states and Stroop Task. SC can thus be a potential indicator for the effectiveness of MI in helping the student subjects to cope with stress better and to improve their relaxation and attention levels. © 2022 IEEE.