Present article deals with epidemiology and etiopathogenesis of syncope which is an object of interest of various medical specialities. Syncope is defined as sudden temporary loss of consciousness due to cerebral hypoperfusion. Syncope is a symptom of various diseases. Syncope should be differentiated from temporary unconsiousness due to abnormal electrical activity of the brain (epilepsy) or metabolic abnormality (hypoglycaemia). Cerebral hypoperfusion is caused by sudden decline in vascular resistence (systemic vasodilation), sudden decrease in cardiac output or cerebral circulation derangement. From etiological point of view syncope can be of reflex, orthostatic, postprandial, cardial or vascular origin.