The causes include acute respiratory infection, diarrhea, measles and malaria, which together account for 48 percent of child deaths in the developing world, according to the report called World Development Indicators.
"Rapid improvement before 1990 gave hope that mortality rates for infants and children would be cut by two-thirds in the following 25 years," the report said. "But progress slowed almost everywhere in the 1990s."
The report said only 33 countries are on track to reach the 2015 goal of reducing child mortality rates by two-thirds from its 1990 levels. It said only two regions — Latin America and the Caribbean and Europe and Central Asia — may be on track to achieve the target.
Five years ago world leaders outlined a number of development objectives, formally known as the Millennium Development Goals, to achieve by 2015. They include boosting primary school enrollments, removing obstacles to greater numbers of girls going to school and improving health care.
Many countries have made progress toward achieving the goals, but Francois Bourguignon, the bank's chief economist, said: "I must admit many countries are off track and a huge effort is needed" to help them progress toward the 2015 goals. Some nations are more behind schedule than others, particularly in sub-Saharan Africa.
One section of the report tracks progress on all the indicators. It provides evidence that inequalities within countries — between rich and poor, urban and rural and male and female populations — may be as much a barrier to achieving the goals as inequalities between countries.
In India, for example, school attendance rates for the richest 20 percent of the population are twice as high as for the poorest. And in the West African nation of Mali, "the mortality rate of children from poor, rural families is twice as high as those from rich urban ones," the bank report said.
On primary school, the report says, 51 countries have already achieved the goal of complete enrollment of eligible children and seven more, mostly in Latin America, are on track, but progress has been slow in parts of Africa and Asia.
Worldwide, more than 100 million primary-age school children remain out of school, almost 60 percent of them girls.
"This situation endures despite overwhelming evidence that teaching children how to read, write and count can boost economic growth, arrest the spread of AIDS and break the cycle of poverty," the report said.
The 401-page report is full of statistics and charts. But the bank's senior vice president for human development, Jean-Louis Sarbib, reminded that "behind every statistic is a person, a child, an orphan, a mother."