The U.N.’s children’s agency, UNICEF, reported the statistic Friday.
More than 9,800 people have died since government forces and Russia-backed separatist rebels began fighting in April 2014. UNICEF says 1.7 million other people have been displaced.
WATCH: New drone footage shows aftermath of shelling in east Ukraine
Fighting has escalated this month in the worst outbreak since a 2015 peace deal.
UNICEF says thousands of children live in areas subjected to shelling, and about one in five eastern Ukrainian schools have been damaged or destroyed.
The U.N. says 3.8 million people need aid due to the conflict. The world body has a $214 humanitarian plan for Ukraine this year. Less than $3 million has been collected so far.