Abstract: The sudden infant death syndrome (SIDS) in the Federal Republic of Germany Han been reviewed. SIDS occurred in infants who looked healthy. The prevalence of SIDS was 2-5‰, in health children and 16.5% in inlant autopsy, most of which were under 6 mounths in age. The epidemiology, the pathology and the pathogenesis have been disscused. Sithypotheses of pathogenesis were recomme- nded as follow; 1.the deficiency in immunologica function; 2.the metabolc distu rbance; 3.the reflex mechanism of vegetative nerve system; 4.the low adaptability of respiro-cardiovascular; 5.the infection; 6.the multiple factors.