There has been an increasing interest in pranayamic breathing exercises which have been known to improve the quality of life. Present study was conducted to find out the effect of Bhastrika and Anulom Vilom Pranayam and yogasana on heart rate variability, general well being, cognition and anxiety levels of the medical students. Ninety-six medical students were randomly divided into two groups. One group performed Bhastrika and Anulom Vilom Pranayam and the second Suryanamaskar for six weeks. The subjects were made to fill in PGI memory scale, Hamilton- anxiety scale and psychological general well being schedule and recording of heart rate variability parameters was done, before and after six weeks of pranayam practice. The results showed highly significant increase in high frequency (HF) components of heart rate variability and decrease in low frequency (LF) components and LF/HF inthe group practising pranayam. There was also highly significant improvement of cognition, general well being and anxiety as shown by the PGI memory scale, Hamilton- anxiety scale and psychological general well being schedule scores in this group. In the yogasana group no significant changes were observed in the heart rate variability, cognition and anxiety although psychological general well being schedule scores significantly improved after six weeks practice of yogasana. The study shows that practice of slow breathing type of pranayam for six weeks improves cognition, anxiety and general well being and Increases the parasympathetic activity. Whereas there was no effect of the yogasana on the above parameters except improvements in the general well being.