This review describes the morphology, microscopy, traditional and folklore uses, phyto-constituents, pharmacological reports, clinical applications and toxicological reports of the prominent species of the genus Passiflora. Flavonoids, glycosides, alkaloids, phenolic compounds and volatile constituents have been reported as the major phyto-constituents of the Passiflora species. A few species of Passiflora have been used for curing various ailments, the most important being Passiflora incarnata Linneaus which possesses significant CNS depressant properties. The studies performed by the authors with the newly isolated benzoflavone (BZF) moiety from P. incarnata have been discussed. In the concluding part, various virgin areas of research on the species of this genus have been highlighted with a view to explore, isolate and identify the medicinally important phyto-constituents which could be utilized to alleviate various diseases affecting the mankind.