During the past two decades tremendous efforts have been made by the medical community, especially in the fields of forensic medicine and pediatrics, to better understand the etiology, epidemiology and pathophysiology of SIDS. There have been many SIDS reports from developed countries, but few from developing Asian countries. Despite a recent significant decrease in the incidence of SIDS in many developed countries, SIDS continues to be the most common cause of post-neonatal infant death in these countries. This article analyzes the SIDS data (1990-2006) from the Office of the Chief Medical Examiner for the State of Maryland, USA, along with review of the literature with regard to the history, epidemiological and pathophysiological characteristics of SIDS, as well as the recent advances in SIDS research. The changing trends in the diagnosis of SIDS and current challenges to its forensic investigation are also discussed.