The objective of our study was to identify the causes of death in children <15 years of age in Inner Mongolia and to examine the age-specific causes of death. Study data from 2008–2012 were obtained from the Death Registry System that is maintained by the Inner Mongolia Centers for Disease Control and Prevention. The mortality rate (per 100,000) for children <15 years of age was calculated and stratified by age in different years. We computed the proportion of age-specific causes of death for children <15 years that occurred between 2008 and 2012 across eight monitoring points in Inner Mongolia. We used a log-linear model to analyze the year and age effects on childhood mortality. From 2008-2012, the standardized mortality of children <15 years of age was 42.78/100,000. The mortality rate was not significantly different from 2008 to 2012 (p>0.05); the mortality rate was the highest in the <1-year age group (p<0.05); and the mortality rate of the <1-year age group was higher in 2012 compared to that in 2009 (p<0.05), 2010 (p<0.05), and 2011 (p<0.05). In children aged 1-14 years, the leading cause of death was injuries, among which transport accident injuries were the most prevalent. To reduce the childhood mortality rate in Inner Mongolia, China, we should focus on the prevention of perinatal deaths in infants <1 year of age and on the prevention of transport accident injuries among older children (1-14 years).