The paper presents and discusses the age pattern of mortality observed in Ngayokheme (Sine Saloum, Senegal). It is compared to data of other developing areas and to model life tables. Mortality at ages 1 to 4 is shown to be much higher than anywhere else where data are available. Reasons for this pattern are investigated. Emphasis is given to the epidemiological pattern, especially to diarrheal diseases and malaria and to the seasonality of mortality.