The activities of recording and reporting causes of death through Mortality Registration System, whichcarried out regularly, complete, and pfocedurally will be able to provide reliable information to assessintervention activity against prevention of disease. This paper aim to find out the pattern of leading of causeof death in infant and underfive children. Study location selected in 12 districts/cities spread all overIndonesia. Sample taken from secondary data selected by stratified random sampling through 3 phases:phase 1, Indonesia is divided into 5 regions. Phase 2, each region is divided according to the City andCounty. Phase 3, each/city district good and poor performance stratified based on IPKM and 30 percent ofthe total sample for the City and 70 percent for the county are randomly selected. The sample size wascalculated using the life table (strata of death) with a high level of child and adult mortality, with a range of95% and a relative standard error of 15%. The sample size is approximately 2 million per region. Thenumber of deaths of infants (0-I years) is 1517 deaths and children under 5 years are 332 deaths. Theproportion of neonatal deaths are 56 percent of total deaths 0-5 years, post- neonatal mortality 10.6 percentof the total deaths 0-5 years. The proportion of children deaths are 1.3 percent of the total deaths. The causeof death of newborus up to 6 days old are low birth weight (21.3 percent), asphyxia (17.3 percent), Respiratory Distress of Newborn(RDS) (11 percent) and 5.9' percent of neonatal sepsis. The highest causeof death of infants aged 7-28 days is pneumonia (34.5 percent), followed by neonatal sepsis (10.2 percent), congenital abnormalities (8.6 percent). The cause of death in infants aged 29 days to 11 months wasdominated by infectious diseases such as pneumonia (29.5 percent) and diarrhea (11 percent). The cause ofdeath of children agedIto 4 years dominated by pneumonia (12.3 percent) and diarrhea (8.7 percent). Ingeneral the highest proportion of cause of death on infant and children under five years are pneumonia anddiarrhea.